|
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%% Papers Published
@article{fds372799,
Author = {Wiley, B},
Title = {Introduction: Chemical, physical and mechanical properties
of nanomaterials},
Pages = {V1-382-V1-382},
Booktitle = {Encyclopedia of Nanomaterials},
Year = {2023},
Month = {January},
ISBN = {9780128224236},
url = {http://dx.doi.org/10.1016/B978-0-12-822425-0.00115-9},
Doi = {10.1016/B978-0-12-822425-0.00115-9},
Key = {fds372799}
}
%% Preprints
@article{fds350225,
Author = {Pegues, H and Tong, H and Wiley, BJ and Samei, E and Lo,
JY},
Title = {CT phantom with 3D anthropomorphic, contrast-enhanced
texture},
Journal = {Progress in Biomedical Optics and Imaging - Proceedings of
SPIE},
Volume = {11312},
Year = {2020},
Month = {January},
ISBN = {9781510633919},
url = {http://dx.doi.org/10.1117/12.2549734},
Abstract = {Physical phantoms with realistic anatomical texture and
composition (including contrast media) are of high value and
relevance in evaluating the performance of clinical computed
tomography (CT) imaging systems. They can offer assessments
of image quality in a manner that is more relevant than
existing phantoms. The goal of this project was to fabricate
anatomically structured 3-D liver texture with added
contrast-enhancement. The study used an inkjet printer and
customized ink. Patient-informed liver texture with contrast
details was first defined computationally and the needed
material for each tissue type was estimated for each voxel
to produce attenuations from -200 to +300 HU, with subtle
5-20 HU lesions. Volumetric data were printed, one sheet of
paper at a time, using “soft tissue” ink based on
200mg/cc sodium bromide (NaBr), and “enhanced tissue”
ink based on Isovue-300. The phantom was scanned on a
commercial CT system (Siemens SOMATOM Definition Flash)
using a clinical protocol. The results show targeted
heterogeneity and enhancement as designed with subtle
artifacts associated with uneven air contamination. In
ongoing work, we plan to use this method to create
anatomically and morphologically accurate liver and lung
lesions with texture for use in dual energy
CT.},
Doi = {10.1117/12.2549734},
Key = {fds350225}
}
@article{fds348582,
Author = {Tong, H and Pegues, H and Yang, F and Samei, E and Lo, JY and Wiley,
BJ},
Title = {Controlling the position-dependent contrast of 3D printed
physical phantoms with a single material},
Journal = {Progress in Biomedical Optics and Imaging - Proceedings of
SPIE},
Volume = {10948},
Year = {2019},
Month = {January},
ISBN = {9781510625433},
url = {http://dx.doi.org/10.1117/12.2513469},
Abstract = {Custom 3D printed physical phantoms are desired for testing
the limits of medical imaging, and for providing
patientspecific information. This work focuses on the
development of low-cost, open source fused filament
fabrication for printing of physical phantoms with the
structure and contrast of human anatomy in computed
tomography (CT) images. Specifically, this paper introduces
the concept of using a porous 3D printed layer as a
background into which additional material can be printed to
control the position-dependent contrast. By using this
method, eight levels of contrast were printed with a single
material.},
Doi = {10.1117/12.2513469},
Key = {fds348582}
}
@article{fds348574,
Author = {Pegues, H and Knudsen, J and Tong, H and Gehm, ME and Wiley, BJ and Samei,
E and Lo, JY},
Title = {Using inkjet 3D printing to create contrast-enhanced
textured physical phantoms for CT},
Journal = {Progress in Biomedical Optics and Imaging - Proceedings of
SPIE},
Volume = {10948},
Year = {2019},
Month = {January},
ISBN = {9781510625433},
url = {http://dx.doi.org/10.1117/12.2512890},
Abstract = {Anthropomorphic phantoms can serve as anatomically
structured tools for assessing clinical computed tomography
(CT) imaging systems. The aim of this project is to create
highly customized 3D inkjet-printed, contrast-enhanced
physical liver phantoms for use in improving CT imaging
system analysis. The capability of using voxelized print to
create physical phantoms with texture was previously
presented by our lab. Building on that technology, we show
the feasibility of producing iodine enhanced liver phantoms
with varying textures, at resolutions higher than clinical
CT using inkjetprinting. We use a desktop inkjet-printer,
with custom inks to print these paper phantoms. Sodium
bromide (NaBr) ink is used to represent unenhanced tissue,
and potassium iodide (KI) represents contrast-enhanced
tissue. We have shown the feasibility of using 3D
inkjet-printing to create unique, contrast-enhanced liver
phantoms for use in CT. In the future, we plan to expand our
methods and tools to create tissue-equivalent physical
phantoms for other anatomical structures in the abdominal
region.},
Doi = {10.1117/12.2512890},
Key = {fds348574}
}
@article{fds339562,
Author = {Kim, MJ and Alvarez, S and Chen, Z and Fichthorn, KA and Wiley,
BJ},
Title = {Single-Crystal Electrochemistry Reveals Why Metal Nanowires
Grow.},
Journal = {Journal of the American Chemical Society},
Volume = {140},
Number = {44},
Pages = {14740-14746},
Year = {2018},
Month = {November},
url = {http://dx.doi.org/10.1021/jacs.8b08053},
Abstract = {Shape-control is used to tune the properties of metal
nanostructures in applications ranging from catalysts to
touch screens, but the origins of anisotropic growth of
metal nanocrystals in solution are unknown. We show
single-crystal electrochemistry can test hypotheses for why
nanostructures form and predict conditions for anisotropic
growth by quantifying the degree to which different species
cause facet-selective metal deposition. Electrochemical
measurements show disruption of alkylamine monolayers by
chloride ions causes facet-selective Cu deposition. An
intermediate range of chloride concentrations maximizes
facet-selective Cu deposition on single crystals and
produces the highest aspect ratio nanowires in a
solution-phase synthesis. DFT calculations similarly show an
intermediate monolayer coverage of chloride displaces the
alkylamine capping agent from the ends but not the sides of
a nanowire, facilitating anisotropic growth.},
Doi = {10.1021/jacs.8b08053},
Key = {fds339562}
}
@article{fds337997,
Author = {Cardenas, JA and Upshaw, S and Catenaccr, MJ and Wiley, BJ and Franklin,
AD},
Title = {Exploring silver contact morphologies in printed carbon
nanotube thin-film transistors},
Journal = {Device Research Conference - Conference Digest,
DRC},
Volume = {2018-June},
Publisher = {IEEE},
Year = {2018},
Month = {August},
ISBN = {9781538630280},
url = {http://dx.doi.org/10.1109/DRC.2018.8442217},
Abstract = {Demand for ubiquitous and flexible electronics to facilitate
the rapid growth of Internet- of- Things (IoT) technologies
has driven the advancement of printed electronics for
low-cost and high-throughput manufacturing. The carbon
nanotube thin-film transistor (CNT-TFT) is one of the most
promising options for printed electronics due to its
mechanical flexibility, compatibility with low-temperature
fabrication, and relatively high mobility [1]. Meanwhile, Ag
nanoparticles remain the most widely used conductive
material in printed inks due to their superb dispersion
stability, high conductivity, and relatively low cost [2].
However, limited studies have explored the impact of
different printed metallic contacts in CNT-TFTs [3], even
though the contact interfaces are one of the leading factors
limiting performance. In this work, the impact of Ag contact
morphology is studied for the first time by fabricating
hundreds of CNT-TFTs using an aerosol jet printer to
systematically investigate three morphologies (nanoparticle
(NP), nanoflake (NF), and nanowire (NW), as seen in Fig. 1)
and their impact on device performance. Using what is
learned from the contact morphology results, the first
CNT-TFTs printed without removal of the substrate from the
printer (full 'print-in-place' additive devices) are also
demonstrated.},
Doi = {10.1109/DRC.2018.8442217},
Key = {fds337997}
}
@article{fds336320,
Author = {Rossman, A and Catenacci, M and Li, AM and Sauer, TJ and Solomon, J and Gehm, ME and Wiley, BJ and Samei, E and Lo, JY},
Title = {3D printed anthropomorphic physical phantom for mammography
and DBT with high contrast custom materials, lesions, and
uniform chest wall region},
Journal = {Progress in Biomedical Optics and Imaging - Proceedings of
SPIE},
Volume = {10573},
Publisher = {SPIE},
Year = {2018},
Month = {January},
ISBN = {9781510616356},
url = {http://dx.doi.org/10.1117/12.2294519},
Abstract = {Anthropomorphic breast phantoms mimic anatomy to evaluate
the performance of clinical mammography and digital breast
tomosynthesis (DBT) systems. Our goal is to make a phantom
that mimics clinically relevant appearance of a patient to
allow for improved imaging systems and lesion detection. We
previously presented a voxelized 3D printed physical phantom
with breast tissue anatomy and a uniform chest wall for
evaluating standard QC metrics. In the current study, metal
ink resolution patterns were designed for the uniform chest
wall spanning 1.5 to 10 lp/mm to cover the resolution range
of mammography and DBT systems, and including test objects
and fiducial markers for future automated processing. The
previous phantom had a limited range of 36%-64% breast
density using the commercial photopolymer inks TangoPlus and
VeroWhite. Several doped materials were tested with the aim
of increasing the contrast of the fibroglandular breast
tissue in the previous phantom. We created custom-made
photopolymers doped with several materials, including
tungsten, to increase breast density, as well as iodine to
simulate contrast-enhanced lesions. We also measured a new,
commercial photopolymer ink, VeroPureWhite, which
corresponds to 92% breast density. The tungsten-doped
material allows for 33-100% breast density range in the
phantom, more than double the density range in our previous
phantom. To our phantom with normal anatomy, we also added
lesion inserts in the form of 3D-printed mass lesions with
varying sizes and contrasts and uniform, commercially
produced iodine inserts to investigate interactions of
lesions without and with contrast in breast
tissue.},
Doi = {10.1117/12.2294519},
Key = {fds336320}
}
@article{fds328562,
Author = {Catenacci, MJ and Flowers, PF and Cao, C and Andrews, JB and Franklin,
AD and Wiley, BJ},
Title = {Fully printed memristors from Cu-SiO2 core-shell
nanowire composites},
Journal = {Device Research Conference - Conference Digest,
DRC},
Publisher = {IEEE},
Year = {2017},
Month = {August},
ISBN = {9781509063277},
url = {http://dx.doi.org/10.1109/DRC.2017.7999482},
Abstract = {An area of printed electronics in which additional
development is necessary is printable non-volatile memory,
which will be essential for the development of fully printed
RFID tags and sensors with integrated data storage.[1] An
approach to making a printable memory is to utilize
materials that exhibit resistive switching; devices based on
this mechanism are often referred to as memristors.[2]
However, existing fully-printed memories using memristors
have properties that do not allow for practical application,
with inadequate cycling endurance (<104 cycles), slow write
speeds (>10 μs), or short retention times (<10 years).[3-5]
These flaws can be attributed that printed switching layers
are thicker and less uniform that those deposited via
vapor-phase methods. Our method of addressing this problem
is to use a composite of copper-silica core-shell nanowires
(Cu-SiO2 NWs). When coated from solution, these devices have
modest switching voltages (2 V), a fast switching speed (50
ns), good endurance (>104 cycles), and data retention times
(4 days) comparable to other fully printed memristors.[6]
This work reports the fabrication and characteristics of a
Cu-SiO2 NW/ethylcellulose composite that is aerosol printed
in a fully-printed memristor array.},
Doi = {10.1109/DRC.2017.7999482},
Key = {fds328562}
}
@article{fds326818,
Author = {Zhao, C and Solomon, J and Sturgeon, GM and Gehm, ME and Catenacci, M and Wiley, BJ and Samei, E and Lo, JY},
Title = {Third generation anthropomorphic physical phantom for
mammography and DBT: Incorporating voxelized 3D printing and
uniform chest wall QC region},
Journal = {Progress in Biomedical Optics and Imaging - Proceedings of
SPIE},
Volume = {10132},
Publisher = {SPIE},
Year = {2017},
Month = {January},
ISBN = {9781510607095},
url = {http://dx.doi.org/10.1117/12.2256091},
Abstract = {Physical breast phantoms provide a standard method to test,
optimize, and develop clinical mammography systems,
including new digital breast tomosynthesis (DBT) systems. In
previous work, we produced an anthropomorphic phantom based
on 500x500x500 μm breast CT data using commercial 3D
printing. We now introduce an improved phantom based on a
new cohort of virtual models with 155x155x155 μm voxels and
fabricated through voxelized 3D printing and dithering,
which confer higher resolution and greater control over
contrast. This new generation includes a uniform chest wall
extension for evaluating conventional QC metrics. The
uniform region contains a grayscale step wedge, chest wall
coverage markers, fiducial markers, spheres, and metal ink
stickers of line pairs and edges to assess contrast,
resolution, artifact spread function, MTF, and other
criteria. We also experimented with doping photopolymer
material with calcium, iodine, and zinc to increase our
current contrast. In particular, zinc was discovered to
significantly increase attenuation beyond 100% breast
density with a linear relationship between zinc
concentration and attenuation or breast density. This linear
relationship was retained when the zinc-doped material was
applied in conjunction with 3D printing. As we move towards
our long term goal of phantoms that are indistinguishable
from patients, this new generation of anthropomorphic
physical breast phantom validates our voxelized printing
process, demonstrates the utility of a uniform QC region
with features from 3D printing and metal ink stickers, and
shows potential for improved contrast via
doping.},
Doi = {10.1117/12.2256091},
Key = {fds326818}
}
@article{fds330267,
Author = {Wiley, B and Chen, J and Sun, Y and Xia, Y},
Title = {Shape-controlled synthesis of metallic nanostructures for
nanocomposites},
Journal = {5th World Congress: Enabling Technologies and New Markets,
Nanocomposites 2005},
Year = {2005},
Month = {January},
Abstract = {To manufacture nanocomposites for macroscopic applications,
a macroscopic amount of nanostructure building blocks is
required. I will present a solution phase synthesis that
produces large quantities of silver, gold, platinum, and
palladium nanostructures with controlled size, shape,
monodispersity, and crystallinity. Some example
nanostrucures include silver nanowires and nanocubes, hollow
gold nanotubes and nanocages, platinum nanowires and
multipods, and palladium nanotubes and nanocages. By
controlling nanostructure size and shape, one can tailor the
photonic, plasmonic, electronic, and catalytic properties of
the metallic nanostructures, and in turn the nanocomposites
in which they are incorporated.},
Key = {fds330267}
}
%% Journal Articles
@article{fds376673,
Author = {Guo, S and Boyarsky, M and Vigil, SA and Yu, Y and Moreno-Hernandez, IA and Gehm, ME and Wiley, BJ},
Title = {Toward One-Way Smoke: Synthesis of Copper-Based Microclubs
with Asymmetric Scattering and Absorption},
Journal = {Advanced Functional Materials},
Year = {2024},
Month = {January},
url = {http://dx.doi.org/10.1002/adfm.202315289},
Abstract = {The ultimate goal of this work is to create an engineered
aerosol that acts as one-way smoke, i.e. it creates an
asymmetric vision environment in which the ability to image
objects depends on the viewing direction. To this end, a
rapid, one-pot synthesis of copper-based microclubs is
developed that consists of a Cu2O octahedron attached to a
Cu2O@Cu shaft. Millions of synthesized particles are
analyzed in minutes with a FlowCam to provide a robust
statistical analysis of their geometry, and rapidly
elucidate the roles of the reaction constituents on the
particle shape and yield. The combination of asymmetry in
both shape and composition introduces a 30% difference in
scattering of light propagating parallel to the microclub
axis from opposing directions. This work represents a first
step toward the creation of an asymmetric imaging
environment with an aerosol consisting of acoustically
aligned microclubs.},
Doi = {10.1002/adfm.202315289},
Key = {fds376673}
}
@article{fds372655,
Author = {Xu, H and Hao, S and Wiley, BJ},
Title = {Anisotropic Growth of Silver Nanocubes: The Role of Bromide
Adsorption and Hydrophilic Polymers},
Journal = {Chemistry of Materials},
Volume = {35},
Number = {17},
Pages = {7196-7207},
Year = {2023},
Month = {September},
url = {http://dx.doi.org/10.1021/acs.chemmater.3c01485},
Abstract = {The application of capping agents to modulate the colloidal
synthesis of metal nanocrystals offers an effective avenue
for shape control, but the roles of such agents are not yet
completely understood. This study uses seed-mediated growth,
single-crystal electrochemistry, and surface-enhanced Raman
spectroscopy (SERS) to illuminate the roles of
polyvinylpyrrolidone (PVP) and bromide (Br-) in the
anisotropic growth of Ag nanocubes. Synthetic results show
that Ag nanocubes only form in the presence of both PVP and
sufficiently high concentrations of Br-. Truncated octahedra
form in the presence of PVP, and truncated cubes form in the
presence of Br- alone. Electrochemical measurements indicate
that elevated concentrations of Br- consistently passivate
Ag(100) facets more than Ag(111) facets regardless of the
presence of PVP. The critical condition for the growth of
cubes, however, materializes only when both PVP and Br- are
present, which sufficiently suppresses atomic deposition to
Ag(100) relative to Ag(111). SERS measurements show that
high concentrations of Br- displace PVP from Ag(100) and
Ag(111), but electrochemical measurements suggest PVP acts
as a strong passivator under such conditions. We propose
that the chemisorption of Br- beneath a physisorbed layer of
PVP creates a unique condition for the growth of Ag
nanocubes. Furthermore, our investigation points to a
generalizable adsorption structure for the synthesis of
{100}-faceted Ag nanocrystals, where Br- adsorption under
other hydrophilic polymers can similarly guide the formation
of Ag nanocubes. This study enhances our understanding of
the synergistic roles of Br- and hydrophilic polymers in the
controlled morphogenesis of Ag nanocrystals.},
Doi = {10.1021/acs.chemmater.3c01485},
Key = {fds372655}
}
@article{fds369678,
Author = {Xu, H and Chen, Z and Hao, S and Fichthorn, KA and Wiley,
BJ},
Title = {Chloride enables the growth of Ag nanocubes and nanowires by
making PVP binding facet-selective.},
Journal = {Nanoscale},
Volume = {15},
Number = {11},
Pages = {5219-5229},
Year = {2023},
Month = {March},
url = {http://dx.doi.org/10.1039/d2nr06762e},
Abstract = {Solution-phase synthesis of metal nanocrystals with multiple
additives is a common strategy for control over nanocrystal
shape, and thus control over their properties. However, few
rules are available to predict the effect of multiple
capping agents on metal nanocrystal shapes, making it hard
to rationally design synthetic conditions. This work uses a
combination of seed-mediated growth, single-crystal
electrochemistry, and DFT calculations to determine the
roles of PVP and Cl<sup>-</sup> in the anisotropic growth of
single-crystal and penta-twinned silver nanocrystals.
Single-crystal seeds grow into truncated octahedra bounded
by a mixture of {111} and {100} facets in the presence of
0.03-30 mM PVP, but when 3-6 μM Cl<sup>-</sup> is added
with PVP, the single-crystal seeds grow into cubes bounded
by {100} facets. Electrochemical measurements on Ag(100) and
Ag(111) single-crystal electrodes show PVP is a capping
agent but it exhibits no selectivity for a particular facet.
Addition of Cl<sup>-</sup> to PVP further passivates Ag(100)
but not Ag(111), leading to conditions that favor formation
of nanocubes. DFT calculations indicate the preferential
binding of Cl<sup>-</sup> to Ag(100) causes preferential
binding of PVP to Ag(100). The combined results indicate the
presence or absence of Cl<sup>-</sup> modulates binding of
PVP to (100) facets, leading to the formation of nanocubes
with Cl<sup>-</sup>, or truncated octahedra without
it.},
Doi = {10.1039/d2nr06762e},
Key = {fds369678}
}
@article{fds363874,
Author = {Koshut, WJ and Kwon, N and Zhao, J and Amendola, A and Wiley, BJ and Gall,
K},
Title = {Flaw sensitivity and tensile fatigue of a high-strength
hydrogel},
Journal = {International Journal of Fatigue},
Volume = {163},
Year = {2022},
Month = {October},
url = {http://dx.doi.org/10.1016/j.ijfatigue.2022.107071},
Abstract = {This work describes mechanical behavior of a high-strength
hydrogel composite relative to costal cartilage. The
materials are analyzed for monotonic ultimate tensile
strength (UTS) with differing flaws that represent extreme
differences in local stress concentration and distribution.
Selected hydrogel and cartilage samples are investigated for
fatigue analysis via cyclic loading. Synthetic hydrogel
samples are more sensitive toward sharp cracks, while
cartilage samples are more sensitive toward cylindrical
holes in fatigue. This work represents a unique tensile
fatigue approach in studying a high-strength soft material
and porcine costal cartilage with and without extreme
defects.},
Doi = {10.1016/j.ijfatigue.2022.107071},
Key = {fds363874}
}
@article{fds366243,
Author = {Zhao, J and Tong, H and Kirillova, A and Koshut, WJ and Malek, A and Brigham, NC and Becker, ML and Gall, K and Wiley,
BJ},
Title = {A Synthetic Hydrogel Composite with a Strength and Wear
Resistance Greater than Cartilage},
Journal = {Advanced Functional Materials},
Volume = {32},
Number = {41},
Year = {2022},
Month = {October},
url = {http://dx.doi.org/10.1002/adfm.202205662},
Abstract = {Key hurdles for replacing damaged cartilage with an
equivalent synthetic construct are the development of a
hydrogel with a strength that exceeds that of cartilage and
fixation of this hydrogel onto the surface of an
articulating joint. This article describes the first
hydrogel with a tensile and compressive strength (51 and
98 MPa) that exceeds those of cartilage (40 and 59 MPa),
and the first attachment of a hydrogel to a metal backing
with a shear strength (2.0 MPa) that exceeds that of
cartilage on bone (1.2 MPa). The hydrogel strength is
achieved through reinforcement of crystallized polyvinyl
alcohol with bacterial cellulose. The high attachment
strength is achieved by securing freeze-dried bacterial
cellulose to a metal backing with an adhesive and a shape
memory alloy clamp prior to infiltration and crystallization
of the polyvinyl alcohol. The bacterial cellulose-reinforced
polyvinyl alcohol is three times more wear resistant than
cartilage over one million cycles and exhibits the same
coefficient of friction. These advances in hydrogel strength
and attachment enable the creation of a hydrogel-based
implant for durable resurfacing of damaged articulating
joints.},
Doi = {10.1002/adfm.202205662},
Key = {fds366243}
}
@article{fds364265,
Author = {Tang, Y and Guo, B and Cruz, MA and Chen, H and Zhou, Q and Lin, Z and Xu, F and Xu, F and Chen, X and Cai, D and Wiley, BJ and Kang,
J},
Title = {Colorful Conductive Threads for Wearable Electronics:
Transparent Cu-Ag Nanonets.},
Journal = {Advanced science (Weinheim, Baden-Wurttemberg,
Germany)},
Volume = {9},
Number = {24},
Pages = {e2201111},
Year = {2022},
Month = {August},
url = {http://dx.doi.org/10.1002/advs.202201111},
Abstract = {Electronic textiles have been regarded as the basic building
blocks for constructing a new generation of wearable
electronics. However, the electronization of textiles often
changes their original properties such as color, softness,
glossiness, or flexibility. Here a rapid room-temperature
fabrication method toward conductive colorful threads and
fabrics with Ag-coated Cu (Cu-Ag) nanonets is demonstrated.
Cu-Ag core-shell nanowires are produced through a one-pot
synthesis followed by electroless deposition. According to
the balance of draining and entraining forces, a fast
dip-withdraw process in a volatile solution is developed to
tightly wrap Cu-Ag nanonets onto the fibers of thread. The
modified threads are not only conductive, but they also
retain their original features with enhanced mechanical
stability and dry-wash durability. Furthermore, various
e-textile devices are fabricated such as a fabric heater,
touch screen gloves, a wearable real-time temperature
sensor, and warm fabrics against infrared thermal
dissipation. These high quality and colorful conductive
textiles will provide powerful materials for promoting
next-generation applications in wearable
electronics.},
Doi = {10.1002/advs.202201111},
Key = {fds364265}
}
@article{fds363875,
Author = {Guo, S and Kim, MJ and Siu, JC and Von Windheim and N and Gall, K and Lin, S and Wiley, BJ},
Title = {Eight-Fold Intensification of Electrochemical
Azidooxygenation with a Flow-Through Electrode},
Journal = {ACS Sustainable Chemistry and Engineering},
Volume = {10},
Number = {23},
Pages = {7648-7657},
Year = {2022},
Month = {June},
url = {http://dx.doi.org/10.1021/acssuschemeng.2c01525},
Abstract = {Finding ways to reduce reactor volume while increasing
product output for electro-organic reactions would
facilitate the broader adoption of such reactions for the
production of chemicals in a commercial setting. This work
investigates how the use of flow with different electrode
structures impacts the productivity (i.e., the rate of
product generation) of a TEMPO-mediated azidooxygenation
reaction. Comparison of a flow and batch process with carbon
paper (CP) demonstrated a 3.8-fold-higher productivity for
the flow reactor. Three custom carbon electrodes, sintered
carbon paper (S-CP), carbon nanofiber (CNF), and composite
carbon microfiber-nanofiber (MNC), were studied in the flow
reactor to evaluate how changing the electrode structure
affected productivity. Under the optimum conditions, these
electrodes achieved productivities 5.4, 6.5, and 7.8 times
higher than the average batch reactor, respectively.
Recycling the outlet from the flow reactor with the MNC
electrode back into the inlet achieved an 81% yield in 36
min, while the batch reactor obtained a 75% yield in 5 h.
These findings demonstrate that the productivity of
electro-organic reactions can be substantially improved
through the use of novel flow-through electrodes.},
Doi = {10.1021/acssuschemeng.2c01525},
Key = {fds363875}
}
@article{fds362438,
Author = {Tong, H and Pegues, H and Samei, E and Lo, JY and Wiley,
BJ},
Title = {Technical note: Controlling the attenuation of 3D-printed
physical phantoms for computed tomography with a single
material.},
Journal = {Med Phys},
Volume = {49},
Number = {4},
Pages = {2582-2589},
Year = {2022},
Month = {April},
url = {http://dx.doi.org/10.1002/mp.15494},
Abstract = {PURPOSE: The purpose of this work was to characterize and
improve the ability of fused filament fabrication to create
anthropomorphic physical phantoms for CT research.
Specifically, we sought to develop the ability to create
multiple levels of X-ray attenuation with a single material.
METHODS: CT images of 3D printed cylinders with different
infill angles and printing patterns were assessed by
comparing their 2D noise power spectra to determine the
conditions that produced minimal and uniform noise. A
backfilling approach in which additional polymer was
extruded into an existing 3D printed background layer was
developed to create multiple levels of image contrast.
RESULTS: A print with nine infill angles and a rectilinear
infill pattern was found to have the best uniformity, but
the printed objects were not as uniform as a commercial
phantom. An HU dynamic range of 600 was achieved by changing
the infill percentage from 40% to 100%. The backfilling
technique enabled control of up to eight levels of contrast
within one object across a range of 200 HU, similar to the
range of soft tissue. A contrast detail phantom with six
levels of contrast and an anthropomorphic liver phantom with
four levels of contrast were printed with a single material.
CONCLUSION: This work improves the uniformity and levels of
contrast that can be achieved with fused filament
fabrication, thereby enabling researchers to easily create
more detailed physical phantoms, including realistic,
anthropomorphic textures.},
Doi = {10.1002/mp.15494},
Key = {fds362438}
}
@article{fds359877,
Author = {Han, S and Kim, J and Lee, Y and Bang, J and Kim, CG and Choi, J and Min, J and Ha, I and Yoon, Y and Yun, C-H and Cruz, M and Wiley, BJ and Ko,
SH},
Title = {Transparent Air Filters with Active Thermal
Sterilization.},
Journal = {Nano letters},
Volume = {22},
Number = {1},
Pages = {524-532},
Year = {2022},
Month = {January},
url = {http://dx.doi.org/10.1021/acs.nanolett.1c02737},
Abstract = {The worldwide proliferation of COVID-19 poses the urgent
need for sterilizable and transparent air filters to inhibit
virus transmission while retaining ease of communication.
Here, we introduce copper nanowires to fabricate transparent
and self-sterilizable air filters. Copper nanowire air
filter (CNAF) allowed visible light penetration, thereby can
exhibit facial expressions, helpful for better
communication. CNAF effectively captured particulate matter
(PM) by mechanical and electrostatic filtration mechanisms.
The temperature of CNAF could be controlled by Joule-heating
up to 100 °C with thermal stability. CNAF successfully
inhibited the growth of <i>E. coli</i> because of the
oligodynamic effect of copper. With heat sterilization, the
antibacterial efficiency against <i>G. anodireducens</i> was
greatly improved up to 99.3% within 10 min. CNAF showed high
reusability with stable filtration efficiency and thermal
antibacterial efficacy after five repeated uses. Our result
suggests an alternative form of active antimicrobial air
filter in preparation for the current and future pandemic
situations.},
Doi = {10.1021/acs.nanolett.1c02737},
Key = {fds359877}
}
@article{fds359878,
Author = {Xu, H and Wiley, BJ},
Title = {The Roles of Citrate and Defects in the Anisotropic Growth
of Ag Nanostructures},
Journal = {Chemistry of Materials},
Volume = {33},
Number = {21},
Pages = {8301-8311},
Year = {2021},
Month = {November},
url = {http://dx.doi.org/10.1021/acs.chemmater.1c02474},
Abstract = {Synthetic control of nanocrystal shape is often achieved by
controlling the crystal structure of the seed crystals as
well as through the use of additives that are thought to
block atomic addition to certain facets. However, the effect
of the crystal structure or additives on the rate of atomic
addition to a specific facet is not usually quantified,
making it difficult to understand and design nanocrystal
syntheses. This article combines single-crystal
electrochemistry measurements with measurements of
anisotropic nanocrystal growth to quantify the roles of
citrate and planar defects in anisotropic atomic addition.
Citrate lowers the rate of atomic addition to Ag(100) and
Ag(111) single crystals by 3.2 and 15 times, respectively.
Citrate decreases the rate of ascorbic acid oxidation in a
facet-selective manner, but citrate decreases the rate of
silver ion reduction to roughly the same extent on Ag(100)
and Ag(111) single crystals. The degree to which citrate
passivates single-crystal electrodes at different citrate
concentrations closely matches the facet-dependent growth
rates for single-crystal seeds. In contrast, seeds with
planar defects exhibit anisotropic growth that is 30-100
times greater than can be explained by the facet-selective
passivation by citrate. Without citrate, more silver
deposits on the edges of seeds with planar defects than in
the middle, but the seeds do not exhibit anisotropic growth.
Evidence suggests that citrate improves the stability of
nanoplates bounded by large {111} facets by preventing
diffusion to {111} facets.},
Doi = {10.1021/acs.chemmater.1c02474},
Key = {fds359878}
}
@article{fds359462,
Author = {Raciti, D and Braun, T and Tackett, BM and Xu, H and Cruz, M and Wiley, BJ and Moffat, TP},
Title = {High-Aspect-Ratio Ag Nanowire Mat Electrodes for
Electrochemical CO Production from CO2},
Journal = {ACS Catalysis},
Volume = {11},
Number = {19},
Pages = {11945-11959},
Year = {2021},
Month = {October},
url = {http://dx.doi.org/10.1021/acscatal.1c02783},
Abstract = {Economic CO2conversion to CO or syngas production requires
product-selective, high-throughput, and durable
electrolyzers. High-surface-area nanocatalysts combined with
gas-diffusion layers (GDLs) enable high CO2flux and
conversion but can suffer from ineffective catalyst
utilization, premature degradation, and flooding of the GDL
that limit electrolyzer operation. Herein, a catalyst layer
(CL) composed of a highly conductive catalyst bed of
high-aspect-ratio Ag nanowire (Ag NW) electrocatalysts is
integrated with a nonconductive porous polytetrafluorethylene
(PTFE) GDL to enable more durable and selective electrolyzer
performance. This platform enables exploration of CL
thickness effects on catalyst utilization efficiency and
selectivity. Combined with a 1-D computational model of the
Ag NW-PTFE GDL, optimized CL thickness was found to be
limited by significant depletion of local aqueous
CO2concentration, resulting in an optimal performance of 250
A/g (15× improvement) and a suppression of the hydrogen
evolution reaction up to 20×. Furthermore, the local pH
within the catalyst microenvironment indicates that local
speciation of the bicarbonate electrolyte influences the
selectivity between H2and CO. Additional experimental
measurements indicate that proton dissociation from
bicarbonate contributes significantly to hydrogen evolution
at intermediate overpotentials. The combination of a
conductive and mechanically stable nanowire catalytic
network with a hydrophobic PTFE porous support structure
provides an effective platform for tuning the
microenvironment of mesoscale catalysts for improved
performance and durability during CO2electroreduction.},
Doi = {10.1021/acscatal.1c02783},
Key = {fds359462}
}
@article{fds356429,
Author = {Pietri, T and Wiley, BJ and Simonato, JP},
Title = {Boron Nitride Nanotubes for Heat Dissipation in
Polycaprolactone Composites},
Journal = {ACS Applied Nano Materials},
Volume = {4},
Number = {5},
Pages = {4774-4780},
Year = {2021},
Month = {May},
url = {http://dx.doi.org/10.1021/acsanm.1c00365},
Abstract = {This article describes the synthesis of nanocomposites for
the fabrication of printable filaments of interest for
additive manufacturing. Boron nitride nanotubes (BNNTs)
stand out from several nanofillers for the improvement of
heat dissipation from polycaprolactone (PCL) nanocomposites.
At 30 wt % BNNT content, a 4-fold increase of the heat
conductivity was measured compared to pristine PCL. However,
such loadings alter the rheological properties in the molten
state, rendering the nanocomposite unprocessable by fused
filament fabrication (FFF) printers. At lower loading (i.e.,
10 wt %), a trade-off was achieved, allowing improved heat
dissipation performance and easy processability. This was
exemplified through a 3D printed radiator as a proof of
concept. The approach described herein could enable the
development of high performance heat dissipation filaments
for FFF fabrication processes.},
Doi = {10.1021/acsanm.1c00365},
Key = {fds356429}
}
@article{fds356117,
Author = {Fichthorn, KA and Chen, Z and Chen, Z and Rioux, RM and Kim, MJ and Wiley,
BJ},
Title = {Understanding the Solution-Phase Growth of Cu and Ag
Nanowires and Nanocubes from First Principles.},
Journal = {Langmuir : the ACS journal of surfaces and
colloids},
Volume = {37},
Number = {15},
Pages = {4419-4431},
Year = {2021},
Month = {April},
url = {http://dx.doi.org/10.1021/acs.langmuir.1c00384},
Abstract = {In this feature article, we provide an account of the
Langmuir Lecture delivered by Kristen Fichthorn at the Fall
2020 Virtual Meeting of the American Chemical Society. We
discuss how multiscale theory and simulations based on
first-principles DFT were useful in uncovering the
intertwined influences of kinetics and thermodynamics on the
shapes of Ag and Cu cubes and nanowires grown in solution.
We discuss how Ag nanocubes can form through PVP-modified
deposition kinetics and how the addition of chloride to the
synthesis can promote thermodynamic cubic shapes for both Ag
and Cu. We discuss kinetic factors contributing to nanowire
growth: in the case of Ag, we show that high-aspect-ratio
nanowires can form as a consequence of Ag atom surface
diffusion on the strained surfaces of Marks-like decahedral
seeds. On the other hand, solution-phase chloride enhances
Cu nanowire growth due to a synergistic interaction between
adsorbed chloride and hexadecylamine (HDA), which leaves the
{111} nanowire ends virtually bare while the {100} sides are
fully covered with HDA. For each of these topics, a synergy
between theory and experiment led to significant
progress.},
Doi = {10.1021/acs.langmuir.1c00384},
Key = {fds356117}
}
@article{fds356118,
Author = {Gálvez-Vázquez, MDJ and Xu, HB and Moreno-García, PA and Hou, YA and Hu, HA and Wiley, BJ and Vesztergom, S and Broekmann,
P},
Title = {Unwrap Them First: Operando Potential- induced
Activation Is Required when Using PVP-Capped Ag Nanocubes as
Catalysts of CO₂ Electroreduction.},
Journal = {Chimia},
Volume = {75},
Number = {3},
Pages = {163-168},
Year = {2021},
Month = {March},
url = {http://dx.doi.org/10.2533/chimia.2021.163},
Abstract = {Metallic nanoparticles of different shape can be used as
efficient electrocatalysts for many technologically and
environmentally relevant processes, like the
electroreduction of CO₂. Intense research is thus targeted
at finding the morphology of nanosized features that best
suits catalytic needs. In order to control the shape and
size distribution of the designed nanoobjects, and to
prevent their aggregation, synthesis routes often rely on
the use of organic capping agents (surfactants). It is
known, however, that these agents tend to remain adsorbed on
the surface of the synthesized nanoparticles and may
significantly impair their catalytic performance, both in
terms of overall yield and of product selectivity. It thus
became a standard procedure to apply certain methods
(<i>e.g</i>. involving UV-ozone or plasma treatments) for
the removal of capping agents from the surface of
nanoparticles, before they are used as catalysts. Proper
design of the operating procedure of the electrocatalysis
process may, however, render such cleaning steps
unnecessary. In this paper we use poly-vinylpyrrolidone
(PVP) capped Ag nanocubes to demonstrate a mere
electrochemical, <i>operando</i> activation method. The
proposed method is based on an observed hysteresis of the
catalytic yield of CO (the desired product of CO₂
electroreduction) as a function of the applied potential.
When as-synthesized nanocubes were directly used for CO₂
electroreduction, the CO yield was rather low at moderate
overpotentials. However, following a potential excursion to
more negative potentials, most of the (blocking) PVP was
irreversibly removed from the catalyst surface, allowing a
significantly higher catalytic yield even under less harsh
operating conditions. The described hysteresis of the
product distribution is shown to be of transient nature, and
following <i>operando</i> activation by a single 'break-in'
cycle, a truly efficient catalyst was obtained that retained
its stability during long hours of operation.},
Doi = {10.2533/chimia.2021.163},
Key = {fds356118}
}
@article{fds354196,
Author = {Kim, MJ and Cruz, MA and Chen, Z and Xu, H and Brown, M and Fichthorn, KA and Wiley, BJ},
Title = {Isotropic Iodide Adsorption Causes Anisotropic Growth of
Copper Microplates},
Journal = {Chemistry of Materials},
Volume = {33},
Number = {3},
Pages = {881-891},
Year = {2021},
Month = {February},
url = {http://dx.doi.org/10.1021/acs.chemmater.0c03596},
Abstract = {Control over the shape of a metal nanostructure grants
control over its properties, but the processes that cause
solution-phase anisotropic growth of metal nanostructures
are not fully understood. This article shows why the
addition of a small amount (75-100 μM) of iodide ions to a
Cu nanowire synthesis results in the formation of Cu
microplates. Microplates are 100 nm thick and micronwide
crystals that are thought to grow through atomic addition to
{100} facets on their sides instead of the {111} facets on
their top and bottom surfaces. Single-crystal
electrochemical measurements show that the addition of
iodide ions decreased the rate of Cu addition to Cu(111) by
8.2 times due to the replacement of adsorbed chloride by
iodide. At the same time, the addition of iodide ions
increased the rate of Cu addition to Cu(100) by 4.0 times
due to the replacement of a hexadecylamine (HDA)
self-assembled monolayer with the adsorbed iodide. The
activation of {100} facets and passivation of {111} facets
with increasing iodide ion concentration correlated with an
increasing yield of microplates. Ab initio thermodynamics
calculations show that, under the experimental conditions, a
minority of iodide ions replaces an overwhelming majority of
chloride and HDA on both Cu(100) and Cu(111). While Cu
nanowire formation is predicted (and observed) in solutions
containing chloride and HDA, the calculations indicate that
a strong thermodynamic driving force occurs for {111} facet
(and microplate) growth when a small amount of iodide is
present, consistent with the experiment.},
Doi = {10.1021/acs.chemmater.0c03596},
Key = {fds354196}
}
@article{fds352377,
Author = {Zhao, J and Kirillova, A and Kelly, CN and Xu, H and Koshut, WJ and Yang,
F and Gall, K and Wiley, BJ},
Title = {High-Strength Hydrogel Attachment through Nanofibrous
Reinforcement.},
Journal = {Advanced healthcare materials},
Volume = {10},
Number = {4},
Pages = {e2001119},
Year = {2021},
Month = {February},
url = {http://dx.doi.org/10.1002/adhm.202001119},
Abstract = {The repair of a cartilage lesion with a hydrogel requires a
method for long-term fixation of the hydrogel in the defect
site. Attachment of a hydrogel to a base that allows for
integration with bone can enable long-term fixation of the
hydrogel, but current methods of forming bonds to hydrogels
have less than a tenth of the shear strength of the
osteochondral junction. This communication describes a new
method, nanofiber-enhanced sticking (NEST), for bonding a
hydrogel to a base with an adhesive shear strength three
times larger than the state-of-the-art. An example of NEST
is described in which a nanofibrous bacterial cellulose
sheet is bonded to a porous base with a hydroxyapatite-forming
cement followed by infiltration of the nanofibrous sheet
with hydrogel-forming polymeric materials. This approach
creates a mineralized nanofiber bond that mimics the
structure of the osteochondral junction, in which collagen
nanofibers extend from cartilage into a mineralized region
that anchors cartilage to bone.},
Doi = {10.1002/adhm.202001119},
Key = {fds352377}
}
@article{fds354576,
Author = {Hou, Y and Kovács, N and Xu, H and Sun, C and Erni, R and Gálvez-Vázquez, MDJ and Rieder, A and Hu, H and Kong, Y and Liu, M and Wiley, BJ and Vesztergom, S and Broekmann, P},
Title = {Limitations of identical location SEM as a method of
degradation studies on surfactant capped nanoparticle
electrocatalysts},
Journal = {Journal of Catalysis},
Volume = {394},
Pages = {58-66},
Year = {2021},
Month = {February},
url = {http://dx.doi.org/10.1016/j.jcat.2020.12.006},
Abstract = {Identical location scanning electron microscopy (IL–SEM)
has become an important tool for electrocatalysis research
in the past few years. The method allows for the observation
of the same site of an electrode, often down to the same
nanoparticle, before and after electrochemical treatment. It
is presumed that by IL–SEM, alterations in the surface
morphology (the growth, shrinkage, or the disappearance of
nanosized features) can be detected, and the thus visualized
degradation can be linked to changes of the catalytic
performance, observed during prolonged electrolyses. In the
rare cases where no degradation is seen, IL–SEM may
provide comfort that the studied catalyst is ready for
up-scaling and can be moved towards industrial applications.
However, although it is usually considered a non-invasive
technique, the interpretation of IL–SEM measurements may
get more complicated. When, for example, IL–SEM is used to
study the degradation of surfactant-capped Ag nanocubes
employed as electrocatalysts of CO2 electroreduction,
nanoparticles subjected to the electron beam during
pre-electrolysis imaging may lose some of their catalytic
activity due to the under-beam formation of a passive
organic contamination layer. Although the entirety of the
catalyst obviously degrades, the spot mapped by IL–SEM
reflects no or little changes during electrolysis. The aim
of this paper is to shed light on an important limitation of
IL–SEM: extreme care is necessary when applying this
method for catalyst degradation studies, especially in case
of nanoparticles with surface-adsorbed capping
agents.},
Doi = {10.1016/j.jcat.2020.12.006},
Key = {fds354576}
}
@article{fds350500,
Author = {Cardenas, JA and Tsang, H and Tong, H and Abuzaid, H and Price, K and Cruz,
MA and Wiley, BJ and Franklin, AD and Lazarus, N},
Title = {Flash ablation metallization of conductive
thermoplastics},
Journal = {Additive Manufacturing},
Volume = {36},
Year = {2020},
Month = {December},
url = {http://dx.doi.org/10.1016/j.addma.2020.101409},
Abstract = {Fused filament fabrication (FFF) is the most widely
available 3D printing technology. Recently, a variety of
conductive thermoplastic filaments have become commercially
available, allowing printing of electronic structures using
the technology. However, the contact interface and
conductivity of these filaments after printing remains
relatively poor, the latter of which is typically at least
four orders of magnitude lower than bulk metal conductors.
While several post-processing approaches exist to enhance
conductivity, they are either user-intensive, time
consuming, or cannot easily be integrated in-line with the
rest of the printing process. In this work, we demonstrate
that exposing conductive composite thermoplastic films (3D
printed or solution-cast) to high-intensity pulsed light
increases their conductance by up to two orders of magnitude
in a manner that is fast, non-contact, and potentially
in-line. This process, referred to as flash ablation
metallization (FAM), is found to vaporize the thermoplastic
matrix on the top surface of a composite film, leaving
behind a metal-dense surface layer. The technique was found
to be effective for a variety of commercial and custom-made
conductive thermoplastic composites, with the largest
response found in Electrifi, a commercial filament
consisting of copper particle loading in a biodegradable
polyester. 3D-printed circuit boards were constructed with
and without FAM exposure, with exposed circuits exhibiting
reduced operating voltages as well as improvements in
reliability.},
Doi = {10.1016/j.addma.2020.101409},
Key = {fds350500}
}
@article{fds353316,
Author = {De Jesus Gálvez-Vázquez and M and Moreno-García, P and Xu, H and Hou,
Y and Hu, H and Montiel, IZ and Rudnev, AV and Alinejad, S and Grozovski,
V and Wiley, BJ and Arenz, M and Broekmann, P},
Title = {Environment Matters: CO2RR Electrocatalyst
Performance Testing in a Gas-Fed Zero-Gap
Electrolyzer},
Journal = {ACS Catalysis},
Volume = {10},
Number = {21},
Pages = {13096-13108},
Year = {2020},
Month = {November},
url = {http://dx.doi.org/10.1021/acscatal.0c03609},
Abstract = {Among the electrolyzers under development for CO2
electroreduction at practical reaction rates, gas-fed
approaches that use gas diffusion electrodes (GDEs) as
cathodes are the most promising. However, the insufficient
long-term stability of these technologies precludes their
commercial deployment. The structural deterioration of the
catalyst material is one possible source of device
durability issues. Unfortunately, this issue has been
insufficiently studied in systems using actual technical
electrodes. Herein, we make use of a morphologically
tailored Ag-based model nanocatalyst [Ag nanocubes (NCs)]
assembled on a zero-gap GDE electrolyzer to establish
correlations between catalyst structures, experimental
environments, electrocatalytic performances, and
morphological degradation mechanisms in highly alkaline
media. The morphological evolution of the Ag-NCs on the GDEs
induced by the CO2 electrochemical reduction reaction
(CO2RR), as well as the direct mechanical contact between
the catalyst layer and anion-exchange membrane, is analyzed
by identical location and post-electrolysis scanning
electron microscopy investigations. We find that at low and
mild potentials positive of -1.8 V versus Ag/AgCl, the
Ag-NCs undergo no apparent morphological alteration induced
by the CO2RR, and the device performance remains stable. At
more stringent cathodic conditions, device failure commences
within minutes, and catalyst corrosion leads to slightly
truncated cube morphologies and the appearance of smaller Ag
nanoparticles. However, comparison with complementary CO2RR
experiments performed in H-cell configurations in a neutral
environment clearly proves that the system failure typically
encountered in the gas-fed approaches does not stem solely
from the catalyst morphological degradation. Instead, the
observed CO2RR performance deterioration is mainly due to
the local high alkalinity that inevitably develops at high
current densities in the zero-gap approach and leads to the
massive precipitation of carbonates which is not observed in
the aqueous environment (H-cell configuration).},
Doi = {10.1021/acscatal.0c03609},
Key = {fds353316}
}
@article{fds350502,
Author = {Yang, F and Zhao, J and Koshut, WJ and Watt, J and Riboh, JC and Gall, K and Wiley, BJ},
Title = {A Synthetic Hydrogel Composite with the Mechanical Behavior
and Durability of Cartilage},
Journal = {Advanced Functional Materials},
Volume = {30},
Number = {36},
Year = {2020},
Month = {September},
url = {http://dx.doi.org/10.1002/adfm.202003451},
Abstract = {This article reports the first hydrogel with the strength
and modulus of cartilage in both tension and compression,
and the first to exhibit cartilage-equivalent tensile
fatigue strength at 100 000 cycles. These properties are
achieved by infiltrating a bacterial cellulose (BC)
nanofiber network with a poly(vinyl alcohol)
(PVA)–poly(2-acrylamido-2-methyl-1-propanesulfonic acid
sodium salt) (PAMPS) double network hydrogel. The BC
provides tensile strength in a manner analogous to collagen
in cartilage, while the PAMPS provides a fixed negative
charge and osmotic restoring force similar to the role of
aggrecan in cartilage. The hydrogel has the same aggregate
modulus and permeability as cartilage, resulting in the same
time-dependent deformation under confined compression. The
hydrogel is not cytotoxic, has a coefficient of friction 45%
lower than cartilage, and is 4.4 times more wear-resistant
than a PVA hydrogel. The properties of this hydrogel make it
an excellent candidate material for replacement of damaged
cartilage.},
Doi = {10.1002/adfm.202003451},
Key = {fds350502}
}
@article{fds352624,
Author = {Brown, M and Wiley, BJ},
Title = {Bromide Causes Facet-Selective Atomic Addition in Gold
Nanorod Syntheses},
Journal = {Chemistry of Materials},
Volume = {32},
Number = {15},
Pages = {6410-6415},
Year = {2020},
Month = {August},
url = {http://dx.doi.org/10.1021/acs.chemmater.0c01494},
Abstract = {The aspect ratio-dependent properties of gold nanorods are
used in a variety of applications, but the cause of
anisotropic nanorod growth remains unclear. Measurements
utilizing single-crystal electrodes were collected to
determine what additive(s) in pentatwinned gold nanorod
syntheses are responsible for facet-selective atomic
addition. With cetyltrimethylammonium in the absence of
bromide, the rate of atomic addition to Au(100) and Au(111)
single crystals was the same, and isotropic nanoparticles
were produced. The addition of increasing concentrations of
bromide suppressed the rate of atomic addition to Au(100)
relative to Au(111) and increased the aspect ratio of gold
nanorods. Bromide was a more effective passivator of Au(100)
in the absence of cetyltrimethylammonium, indicating
cetyltrimethylammonium does not cause facet-selective atomic
addition. Cetyltrimethylammonium surfactant is still
necessary for gold nanorod growth because it reduces the
rate of gold ion reduction and stabilizes suspended
nanoparticles against aggregation.},
Doi = {10.1021/acs.chemmater.0c01494},
Key = {fds352624}
}
@article{fds349892,
Author = {Yang, F and Kim, MJ and Brown, M and Wiley, BJ},
Title = {Alkaline Water Electrolysis at 25 A cm−2 with a
Microfibrous Flow-through Electrode},
Journal = {Advanced Energy Materials},
Volume = {10},
Number = {25},
Year = {2020},
Month = {July},
url = {http://dx.doi.org/10.1002/aenm.202001174},
Abstract = {The generation of renewable electricity is variable, leading
to periodic oversupply. Excess power can be converted to H2
via water electrolysis, but the conversion cost is currently
too high. One way to decrease the cost of electrolysis is to
increase the maximum productivity of electrolyzers. This
study investigates how nano- and microstructured porous
electrodes can improve the productivity of H2 generation in
a zero-gap, flow-through alkaline water electrolyzer. Three
nickel electrodes—foam, microfiber felt, and nanowire
felt—are studied to examine the tradeoff between surface
area and pore structure on the performance of alkaline
electrolyzers. Although the nanowire felt with the highest
surface area initially provides the highest performance,
this performance quickly decreases as gas bubbles are
trapped within the electrode. The open structure of the foam
facilitates bubble removal, but its small surface area
limits its maximum performance. The microfiber felt exhibits
the best performance because it balances high surface area
with the ability to remove bubbles. The microfiber felt
maintains a maximum current density of 25 000 mA cm−2 over
100 h without degradation, which corresponds to a hydrogen
production rate 12.5- and 50-times greater than conventional
proton-exchange membrane and alkaline electrolyzers,
respectively.},
Doi = {10.1002/aenm.202001174},
Key = {fds349892}
}
@article{fds350501,
Author = {Manning, HG and Flowers, PF and Cruz, MA and Rocha, CGD and Callaghan,
CO and Ferreira, MS and Wiley, BJ and Boland, JJ},
Title = {The resistance of Cu nanowire-nanowire junctions and
electro-optical modeling of Cu nanowire networks},
Journal = {Applied Physics Letters},
Volume = {116},
Number = {25},
Year = {2020},
Month = {June},
url = {http://dx.doi.org/10.1063/5.0012005},
Abstract = {Flexible transparent conductors made from networks of
metallic nanowires are a potential replacement for
conventional, non-flexible, and transparent conducting
materials such as indium tin oxide. Cu nanowires are
particularly interesting as cost-effective alternatives to
Ag nanowires - the most investigated metallic nanowire to
date. To optimize the conductivity of Cu nanowire networks,
the resistance contributions from the material and nanowire
junctions must be independently known. In this paper, we
report the resistivity values (ρ) of individual
solution-grown Cu nanowires «ρ»= 20.1 ± 1.3 nω m and
the junction resistance (Rjxn) between two overlapping Cu
nanowires «Rjxn»= 205.7 ± 57.7 ω. These electrical data
are incorporated into an electro-optical model that
generates analogs for Cu nanowire networks, which accurately
predict without the use of fitting factors the optical
transmittance and sheet resistance of the transparent
electrode. The model's predictions are validated using
experimental data from the literature of Cu nanowire
networks composed of a wide range of aspect ratios (nanowire
length/diameter). The separation of the material resistance
and the junction resistance allows the effectiveness of
post-deposition processing methods to be evaluated, aiding
research and industry groups in adopting a
materials-by-design approach.},
Doi = {10.1063/5.0012005},
Key = {fds350501}
}
@article{fds347325,
Author = {Kim, MJ and Brown, M and Wiley, BJ},
Title = {Electrochemical investigations of metal nanostructure growth
with single crystals.},
Journal = {Nanoscale},
Volume = {11},
Number = {45},
Pages = {21709-21723},
Year = {2019},
Month = {November},
url = {http://dx.doi.org/10.1039/c9nr05782j},
Abstract = {Control over the nanoscopic structure of a material allows
one to tune its properties for a wide variety of
applications. Colloidal synthesis has become a convenient
way to produce anisotropic metal nanostructures with a
desired set of properties, but in most syntheses, the
facet-selective surface chemistry causing anisotropic growth
is not well-understood. This review highlights the recent
use of electrochemical methods and single-crystal electrodes
to investigate the roles of organic and inorganic additives
in modulating the rate of atomic addition to different
crystal facets. Differential capacitance and
chronocoulometric techniques can be used to extract
thermodynamic data on how additives selectively adsorb,
while mixed potential theory can be used to observe the
effect of additives on the rate of atomic addition to a
specific facet. Results to date indicate that these
experimental methods can provide new insights into the role
capping agents and halides play in controlling anisotropic
growth.},
Doi = {10.1039/c9nr05782j},
Key = {fds347325}
}
@article{fds353041,
Author = {Yurduseven, O and Ye, S and Fromenteze, T and Wiley, BJ and Smith,
DR},
Title = {3d conductive polymer printed metasurface antenna for
fresnel focusing},
Journal = {Designs},
Volume = {3},
Number = {3},
Pages = {1-9},
Year = {2019},
Month = {September},
url = {http://dx.doi.org/10.3390/designs3030046},
Abstract = {We demonstrate a 3D printed holographic metasurface antenna
for beam-focusing applications at 10 GHz within the X-band
frequency regime. The metasurface antenna is printed using a
dual-material 3D printer leveraging a biodegradable
conductive polymer material (Electrifi) to print the
conductive parts and polylactic acid (PLA) to print the
dielectric substrate. The entire metasurface antenna is 3D
printed at once; no additional techniques, such as
metal-plating and laser etching, are required. It is
demonstrated that using the 3D printed conductive polymer
metasurface, high-fidelity beam focusing can be achieved
within the Fresnel region of the antenna. It is also shown
that the material conductivity for 3D printing has a
substantial effect on the radiation characteristics of the
metasurface antenna.},
Doi = {10.3390/designs3030046},
Key = {fds353041}
}
@article{fds343572,
Author = {Lazarus, N and Bedair, SS and Hawasli, SH and Kim, MJ and Wiley, BJ and Smith, GL},
Title = {Selective Electroplating for 3D-Printed Electronics},
Journal = {Advanced Materials Technologies},
Volume = {4},
Number = {8},
Year = {2019},
Month = {August},
url = {http://dx.doi.org/10.1002/admt.201900126},
Abstract = {Creating 3D-printed parts with embedded circuitry is the
next frontier in additive manufacturing, but printing of
conductors with performance comparable to bulk metals such
as copper is a difficult challenge. A hybrid process based
on 3D printing followed by electroplating on highly
conductive thermoplastic filament is used to manufacture 3D
circuit boards and electronic packaging. Dual extruder heads
on a standard fused filament fabrication printer are used to
selectively define regions for electroplating, allowing
distinct traces and multiple materials to be patterned in
the same 3D-printed parts. Using this approach, a 3D-printed
surface-mount package and a 555 timer oscillator circuit are
demonstrated, including soldering of components onto the
electroplated copper surface.},
Doi = {10.1002/admt.201900126},
Key = {fds343572}
}
@article{fds342466,
Author = {Kim, MJ and Cruz, MA and Yang, F and Wiley, BJ},
Title = {Accelerating electrochemistry with metal
nanowires},
Journal = {Current Opinion in Electrochemistry},
Volume = {16},
Pages = {19-27},
Year = {2019},
Month = {August},
url = {http://dx.doi.org/10.1016/j.coelec.2019.03.005},
Abstract = {Scalable, solution-phase syntheses of metal nanowires are
enabling their increased use in electrochemical processes.
This review highlights recent results demonstrating how
metal nanowires can exhibit better durability and higher
activity than traditional metal nanoparticle
electrocatalysts on carbon supports. Metal nanowires can
also form interconnected two-dimensional and
three-dimensional (3D) networks that eliminate the need for
a carbon support, thus eliminating the detrimental effects
of carbon corrosion. Porous 3D networks of nanowires can be
used as flow-through electrodes with the highest specific
surface areas and mass transport coefficients obtained to
date, enabling dramatic increases in the productivity of
electrochemical reactions. Nanowire networks are also
serving as 3D current collectors that improve the capacity
of batteries. The tunable surface structure and dimensions
of metal nanowires offer researchers a new opportunity to
create electrodes that are tailored from the atomic scale to
the microscale to improve electrochemical
performance.},
Doi = {10.1016/j.coelec.2019.03.005},
Key = {fds342466}
}
@article{fds342126,
Author = {Huo, D and Kim, MJ and Lyu, Z and Shi, Y and Wiley, BJ and Xia,
Y},
Title = {One-Dimensional Metal Nanostructures: From Colloidal
Syntheses to Applications.},
Journal = {Chemical reviews},
Volume = {119},
Number = {15},
Pages = {8972-9073},
Year = {2019},
Month = {August},
url = {http://dx.doi.org/10.1021/acs.chemrev.8b00745},
Abstract = {This Review offers a comprehensive review of the colloidal
synthesis, mechanistic understanding, physicochemical
properties, and applications of one-dimensional (1D) metal
nanostructures. After a brief introduction to the different
types of 1D nanostructures, we discuss major concepts and
methods typically involved in a colloidal synthesis of 1D
metal nanostructures, as well as the current mechanistic
understanding of how the nanostructures are formed. We then
highlight how experimental studies and computational
simulations have expanded our knowledge of how and why 1D
metal nanostructures grow. Following specific examples of
syntheses for monometallic, multimetallic, and
heterostructured systems, we showcase how the unique
structure-property relationships of 1D metal nanostructures
have enabled a broad spectrum of applications, including
sensing, imaging, plasmonics, photonics, display, thermal
management, and catalysis. Throughout our discussion, we
also offer perspectives with regard to the future directions
of development for this class of nanomaterials.},
Doi = {10.1021/acs.chemrev.8b00745},
Key = {fds342126}
}
@article{fds346028,
Author = {Williams, NX and Noyce, S and Cardenas, JA and Catenacci, M and Wiley,
BJ and Franklin, AD},
Title = {Silver nanowire inks for direct-write electronic tattoo
applications.},
Journal = {Nanoscale},
Volume = {11},
Number = {30},
Pages = {14294-14302},
Year = {2019},
Month = {August},
url = {http://dx.doi.org/10.1039/c9nr03378e},
Abstract = {Room-temperature printing of conductive traces has the
potential to facilitate the direct writing of electronic
tattoos and other medical devices onto biological tissue,
such as human skin. However, in order to achieve sufficient
electrical performance, the vast majority of conductive inks
require biologically harmful post-processing techniques. In
addition, most printed conductive traces will degrade with
bending stresses that occur from everyday movement. In this
work, water-based inks consisting of high aspect ratio
silver nanowires are shown to enable the printing of
conductive traces at low temperatures and without harmful
post-processing. Moreover, the traces produced from these
inks retain high electrical performance, even while
undergoing up to 50% bending strain and cyclic bending
strain over a thousand bending cycles. This ink has a rapid
dry time of less than 2 minutes, which is imperative for
applications requiring the direct writing of electronics on
sensitive surfaces. Demonstrations of conductive traces
printed onto soft, nonplanar materials, including an apple
and a human finger, highlight the utility of these new
silver nanowire inks. These mechanically robust films are
ideally suited for printing directly on biological
substrates and may find potential applications in the
direct-write printing of electronic tattoos and other
biomedical devices.},
Doi = {10.1039/c9nr03378e},
Key = {fds346028}
}
@article{fds344802,
Author = {Kim, MJ and Seo, Y and Cruz, MA and Wiley, BJ},
Title = {Metal Nanowire Felt as a Flow-Through Electrode for
High-Productivity Electrochemistry.},
Journal = {ACS nano},
Volume = {13},
Number = {6},
Pages = {6998-7009},
Year = {2019},
Month = {June},
url = {http://dx.doi.org/10.1021/acsnano.9b02058},
Abstract = {Flow-through electrodes such as carbon paper are used in
redox flow batteries, water purification, and electroorganic
syntheses. This work examines the extent to which reducing
the size of the fibers to the nanoscale in a flow-through
electrode can increase the productivity of electrochemical
processes. A Cu nanowire felt, made from nanowires 45 times
smaller than the 10 μm wide fibers in carbon paper, can
achieve a productivity 278 times higher than carbon paper
for mass-transport-limited reduction of Cu ions. Higher
increases in productivity were predicted for the Cu nanowire
felt based on the mass-transport-limited current, but Cu ion
reduction became charge transfer-limited on Cu nanowire felt
at high concentrations and flow rates when the
mass-transport-limited current became comparable to the
charge transfer-limited current. In comparison, the reaction
rate on carbon paper was mass-transport-limited under all
concentrations and flow rates because its
mass-transport-limited current was much lower than its
charge transfer-limited current. Higher volumetric
productivities were obtained for the Cu nanowire felt by
switching from Cu ion reduction to Alizarin Red S (ARS)
reduction, which has a higher reaction rate constant. An
electroorganic intramolecular cyclization reaction with Cu
nanowire felt achieved a productivity 4.2 times higher than
that of carbon paper, although this reaction was also
affected by charge transfer kinetics. This work demonstrates
that large gains in productivity can be achieved with
nanostructured flow-through electrodes, but the potential
gains can be limited by the charge transfer kinetics of a
reaction.},
Doi = {10.1021/acsnano.9b02058},
Key = {fds344802}
}
@article{fds346256,
Author = {Kim, MJ and Cruz, MA and Ye, S and Gray, AL and Smith, GL and Lazarus, N and Walker, CJ and Sigmarsson, HH and Wiley, BJ},
Title = {One-step electrodeposition of copper on conductive 3D
printed objects},
Journal = {Additive Manufacturing},
Volume = {27},
Pages = {318-326},
Year = {2019},
Month = {May},
url = {http://dx.doi.org/10.1016/j.addma.2019.03.016},
Abstract = {3D printing with electrically conductive filaments enables
rapid prototyping and fabrication of electronics, but the
performance of such devices can be limited by the fact that
the most conductive thermoplastic-based filaments for 3D
printing are 3750 times less conductive than copper. This
study explores the use of one-step electrodeposition of
copper onto electrically conductive 3D printed objects as a
way to improve their conductivity and performance.
Comparison of three different commercially-available
conductive filaments demonstrates that only the most
conductive commercially available filament could enable
one-step electrodeposition of uniform copper films.
Electrodeposition improved the electrical conductivity and
the ampacity of 3D printed traces by 94 and 17 times
respectively, compared to the as-printed object. The areal
surface roughness of the objects was reduced from 9.3 to 6.9
μm after electrodeposition, and a further reduction in
surface roughness to 3.9 μm could be achieved through the
addition of organic additives to the electrodeposition bath.
Copper electrodeposition improved the quality factor of a 3D
printed inductor by 1740 times and the gain of a 3D printed
horn antenna by 1 dB. One-step electrodeposition is a fast
and simple way to improve the conductivity and performance
of 3D printed electronic components.},
Doi = {10.1016/j.addma.2019.03.016},
Key = {fds346256}
}
@article{fds366363,
Author = {Rossman, AH and Catenacci, M and Zhao, C and Sikaria, D and Knudsen, JE and Dawes, D and Gehm, ME and Samei, E and Wiley, BJ and Lo,
JY},
Title = {Three-dimensionally-printed anthropomorphic physical phantom
for mammography and digital breast tomosynthesis with custom
materials, lesions, and uniform quality control
region.},
Journal = {J Med Imaging (Bellingham)},
Volume = {6},
Number = {2},
Pages = {021604},
Year = {2019},
Month = {April},
url = {http://dx.doi.org/10.1117/1.JMI.6.2.021604},
Abstract = {Anthropomorphic breast phantoms mimic patient anatomy in
order to evaluate clinical mammography and digital breast
tomosynthesis system performance. Our goal is to create a
modular phantom with an anthropomorphic region to allow for
improved lesion and calcification detection as well as a
uniform region to evaluate standard quality control (QC)
metrics. Previous versions of this phantom used commercial
photopolymer inkjet three-dimensional printers to recreate
breast anatomy using four surfaces that were fabricated with
commercial materials spanning only a limited breast density
range of 36% to 64%. We use modified printers to create
voxelized, dithered breast phantoms with continuous
gradations between glandular and adipose tissues. Moreover,
the new phantom replicates the low-end density (representing
adipose tissue) using third party material, Jf Flexible, and
increases the high-end density to the density of glandular
tissue and beyond by either doping Jf Flexible with salts
and nanoparticles or using a new commercial resin,
VeroPureWhite. An insert design is utilized to add masses,
calcifications, and iodinated objects into the phantom for
increased utility. The uniform chest wall region provides a
space for traditional QC objects such as line pair patterns
for measuring resolution and scale bars for measuring
printer linearity. Incorporating these distinct design
modules enables us to create an improved, complete breast
phantom to better evaluate clinical mammography systems for
lesion and calcification detection and standard QC
performance evaluation.},
Doi = {10.1117/1.JMI.6.2.021604},
Key = {fds366363}
}
@article{fds339814,
Author = {Cardenas, JA and Upshaw, S and Williams, NX and Catenacci, MJ and Wiley,
BJ and Franklin, AD},
Title = {Impact of Morphology on Printed Contact Performance in
Carbon Nanotube Thin-Film Transistors},
Journal = {Advanced Functional Materials},
Volume = {29},
Number = {1},
Pages = {1805727-1805727},
Publisher = {WILEY},
Year = {2019},
Month = {January},
url = {http://dx.doi.org/10.1002/adfm.201805727},
Abstract = {Silver nanoparticles (NPs) are the most widely used
conductive material throughout the printed electronics space
due to their high conductivity and low cost. However, when
interfacing with other prominent printed materials, such as
semiconducting carbon nanotubes (CNTs) in thin-film
transistors (TFTs), silver is suboptimal when compared to
more expensive or less conductive materials. Consequently,
there would be significant value to improving the interface
of printed silver to CNT films. In this work, the impact of
nanostructure morphology on the electrical properties of
printed silver and nanotube junctions in CNT-TFTs is
investigated. Three distinct silver morphologies (NPs,
nanoflakes – NFs, and nanowires – NWs) are explored with
top- and bottom-contact configurations for each. The NF
morphology in a top-contact configuration is found to yield
the best electrical interface to CNTs, resulting in an
average contact resistance of 1.2 MΩ ⋅ µm. Beyond
electrical performance, several trade-offs in morphology
selection are revealed, including print resolution and
process temperature. While NF inks produce the best
interfaces, NP inks produce the smallest features, and NW
inks are compatible with low processing temperatures (<80
°C). These results outline the trade-offs between silver
contact morphologies in CNT-TFTs and show that contact
morphology selection can be tailored for specific
applications.},
Doi = {10.1002/adfm.201805727},
Key = {fds339814}
}
@article{fds343425,
Author = {Reyes, C and Somogyi, R and Niu, S and Cruz, MA and Yang, F and Catenacci,
MJ and Rhodes, CP and Wiley, BJ},
Title = {Three-Dimensional Printing of a Complete Lithium Ion Battery
with Fused Filament Fabrication},
Journal = {ACS Applied Energy Materials},
Volume = {1},
Number = {10},
Pages = {5268-5279},
Year = {2018},
Month = {October},
url = {http://dx.doi.org/10.1021/acsaem.8b00885},
Abstract = {The ability to 3D print lithium ion batteries (LIBs) in an
arbitrary geometry would not only allow the battery form
factor to be customized to fit a given product design but
also facilitate the use of the battery as a structural
component. A major hurdle to achieving this goal is the low
ionic conductivity of the polymers used for 3D printing.
This article reports the development of anode, cathode, and
separator materials that enable 3D printing of complete
lithium ion batteries with low cost and widely available
fused filament fabrication (FFF) 3D printers. Poly(lactic
acid) (PLA) was infused with a mixture of ethyl methyl
carbonate, propylene carbonate, and LiClO4 to obtain an
ionic conductivity of 0.085 mS cm-1, a value comparable to
that of polymer and hybrid electrolytes. Different
electrically conductive (Super P, graphene, multiwall carbon
nanotubes) and active (lithium titanate, lithium manganese
oxide) materials were blended into PLA to determine the
relationships among filler loading, conductivity, charge
storage capacity, and printability. Up to 30 vol % of solids
could be mixed into PLA without degrading its printability,
and an 80:20 ratio of conductive to active material
maximized the charge storage capacity. The highest capacity
was obtained with lithium titanate and graphene
nanoplatelets in the anode, and lithium manganese oxide and
multiwall carbon nanotubes in the cathode. We demonstrate
the use of these novel materials in a fully 3D printed coin
cell, as well as 3D printed wearable electronic devices with
integrated batteries.},
Doi = {10.1021/acsaem.8b00885},
Key = {fds343425}
}
@article{fds337386,
Author = {Manning, HG and Niosi, F and da Rocha, CG and Bellew, AT and O'Callaghan, C and Biswas, S and Flowers, PF and Wiley, BJ and Holmes,
JD and Ferreira, MS and Boland, JJ},
Title = {Emergence of winner-takes-all connectivity paths in random
nanowire networks.},
Journal = {Nature communications},
Volume = {9},
Number = {1},
Pages = {3219},
Year = {2018},
Month = {August},
url = {http://dx.doi.org/10.1038/s41467-018-05517-6},
Abstract = {Nanowire networks are promising memristive architectures for
neuromorphic applications due to their connectivity and
neurosynaptic-like behaviours. Here, we demonstrate a
self-similar scaling of the conductance of networks and the
junctions that comprise them. We show this behavior is an
emergent property of any junction-dominated network. A
particular class of junctions naturally leads to the
emergence of conductance plateaus and a "winner-takes-all"
conducting path that spans the entire network, and which we
show corresponds to the lowest-energy connectivity path. The
memory stored in the conductance state is distributed across
the network but encoded in specific connectivity pathways,
similar to that found in biological systems. These results
are expected to have important implications for development
of neuromorphic devices based on reservoir
computing.},
Doi = {10.1038/s41467-018-05517-6},
Key = {fds337386}
}
@article{fds336317,
Author = {Reyes, C and Fu, L and Suthanthiraraj, PPA and Owens, CE and Shields,
CW and López, GP and Charbonneau, P and Wiley, BJ},
Title = {The Limits of Primary Radiation Forces in Bulk Acoustic
Standing Waves for Concentrating Nanoparticles},
Journal = {Particle and Particle Systems Characterization},
Volume = {35},
Number = {7},
Pages = {1700470-1700470},
Publisher = {WILEY},
Year = {2018},
Month = {July},
url = {http://dx.doi.org/10.1002/ppsc.201700470},
Abstract = {Acoustic waves are increasingly used to concentrate,
separate, and pattern nanoparticles in liquids, but the
extent to which nanoparticles of different size and
composition can be focused is not well-defined. This article
describes a simple analytical model for predicting the
distribution of nanoparticles around the node of a 1D bulk
acoustic standing wave over time as a function of pressure
amplitude, acoustic contrast factor (i.e., nanoparticle and
fluid composition), and size of the nanoparticles.
Predictions from this model are systematically compared to
results from experiments on gold nanoparticles of different
sizes to determine the model's accuracy in estimating both
the rate and the degree of nanoparticle focusing across a
range of pressure amplitudes. The model is further used to
predict the minimum particle size that can be focused for
different nanoparticle and fluid compositions, and those
predictions are tested with gold, silica, and polystyrene
nanoparticles in water. A procedure combining UV-light and
photoacid is used to induce the aggregation of nanoparticles
to illustrate the effect of nanoparticle aggregation on the
observed degree of acoustic focusing. Overall, these
findings clarify the extent to which acoustic resonating
devices can be used to manipulate, pattern, and enrich
nanoparticles suspended in liquids.},
Doi = {10.1002/ppsc.201700470},
Key = {fds336317}
}
@article{fds332737,
Author = {Cruz, MA and Ye, S and Kim, MJ and Reyes, C and Yang, F and Flowers, PF and Wiley, BJ},
Title = {Multigram Synthesis of Cu-Ag Core–Shell Nanowires Enables
the Production of a Highly Conductive Polymer Filament for
3D Printing Electronics},
Journal = {Particle and Particle Systems Characterization},
Volume = {35},
Number = {5},
Pages = {1700385-1700385},
Publisher = {WILEY},
Year = {2018},
Month = {May},
url = {http://dx.doi.org/10.1002/ppsc.201700385},
Abstract = {This article reports a synthesis that yields 4.4 g of Cu
nanowires in 1 h, and a method to coat 22 g of Cu nanowires
with Ag within 1 h. Due to the large diameters of Cu
nanowires (≈240 nm) produced by this synthesis, a Ag:Cu
mol ratio of 0.04 is sufficient to coat the nanowires with
≈3 nm of Ag, and thereby protect them from oxidation. This
multigram Cu-Ag core–shell nanowire production process
enabled the production of the first nanowire-based
conductive polymer composite filament for 3D printing. The
3D printing filament has a resistivity of 0.002 Ω cm, >100
times more conductive than commercially available
graphene-based 3D printing filaments. The conductivity of
composites containing 5 vol% of 50-µm-long Cu-Ag nanowires
is greater than composites containing 22 vol% of 20-µm-long
Ag nanowires or 10-µm-long flakes, indicating that
high-aspect ratio Cu-Ag nanowires enable the production of
highly conductive composites at relatively low volume
fractions. The highly conductive filament can support
current densities between 2.5 and 4.5 × 105 A m−2
depending on the surface-to-volume ratio of the printed
trace, and was used to 3D print a conductive coil for
wireless power transfer.},
Doi = {10.1002/ppsc.201700385},
Key = {fds332737}
}
@article{fds349487,
Author = {Cardenas, JA and Catenacci, MJ and Andrews, JB and Williams, NX and Wiley, BJ and Franklin, AD},
Title = {In-Place Printing of Carbon Nanotube Transistors at Low
Temperature},
Journal = {ACS Applied Nano Materials},
Volume = {1},
Number = {4},
Pages = {1863-1869},
Year = {2018},
Month = {April},
url = {http://dx.doi.org/10.1021/acsanm.8b00269},
Abstract = {Interest in flexible, stretchable, and wearable electronics
has motivated the development of additive printing to
fabricate customizable devices and systems directly onto
virtually any surface. However, progress has been limited by
the relatively high temperatures (>200 °C) required to
sinter metallic inks and time-consuming process steps, many
of which require removal of the substrate from the printer
for coating, washing, or sintering. In this work, we
addressed these challenges and demonstrate carbon nanotube
thin-film transistors (CNT-TFTs) that are fabricated by
aerosol jet printing with the substrate never leaving the
printer. The full in-place printing approach, from first
step to last, used a maximum process temperature of only 80
°C on the printer platen. Silver nanowire (Ag NW) ink was
found to be most viable for lowerature, in-place sintering
while still yielding good electrical interfaces to the CNT
thin-film channels. These aerosol-jet printed Ag NW films
were conductive immediately after fabrication, which is the
key component enabling rapid and sequential in-place
printing. The devices exhibit on-currents as high as 80
μA/mm, effective mobilities of 12 cm2/(V·s), and on/off
current ratios exceeding 105. These findings provide a
promising path forward toward the additive manufacture of
flexible and stretchable electronics in a low-cost, highly
customizable, and agile manner.},
Doi = {10.1021/acsanm.8b00269},
Key = {fds349487}
}
@article{fds336318,
Author = {Kim, MJ and Alvarez, S and Yan, T and Tadepalli, V and Fichthorn, KA and Wiley, BJ},
Title = {Modulating the Growth Rate, Aspect Ratio, and Yield of
Copper Nanowires with Alkylamines},
Journal = {Chemistry of Materials},
Volume = {30},
Number = {8},
Pages = {2809-2818},
Publisher = {American Chemical Society (ACS)},
Year = {2018},
Month = {April},
url = {http://dx.doi.org/10.1021/acs.chemmater.8b00760},
Abstract = {This article shows how the chain length of alkylamine
capping agents and the corresponding stability of their
self-assembled monolayers on a Cu surface determines the
growth rate, yield, and dimensions of Cu nanowires produced
in a solution-phase synthesis. Of the 10 linear alkylamines
that were tested, only those with 12 or more carbon atoms
induced growth of nanowires. The length, yield, and growth
rate of nanowires were larger for shorter alkylamines. As
the Cu nanowire growth rates were up to 1050 times smaller
than the calculated diffusion-limited growth rates - and the
alkylamine chain length had no significant effect on the in
situ generation of the reducing agent - we conclude the rate
of alkylamine-mediated Cu nanowire growth is limited by
charge transfer. Electrochemical measurements indicate
longer alkylamines form more effective passivation layers
that greatly decrease the rate at which Cu-alkylamine
complexes are reduced onto a Cu surface. Molecular dynamics
simulations show that the energy required for removal of
octadecylamine from a self-assembled monolayer on the Cu
surface is much larger (3.59 eV) than for removal of
tetradecylamine (2.06 eV). Thus, the more stable
self-assembled monolayer formed by longer-chain alkylamines
leads to greater inhibition of Cu addition, slower growth,
reduced yield, and reduced nanowire aspect
ratio.},
Doi = {10.1021/acs.chemmater.8b00760},
Key = {fds336318}
}
@article{fds336319,
Author = {Catenacci, MJ and Reyes, C and Cruz, MA and Wiley,
BJ},
Title = {Stretchable Conductive Composites from Cu-Ag Nanowire
Felt.},
Journal = {ACS nano},
Volume = {12},
Number = {4},
Pages = {3689-3698},
Year = {2018},
Month = {April},
url = {http://dx.doi.org/10.1021/acsnano.8b00887},
Abstract = {Materials that retain a high conductivity under strain are
essential for wearable electronics. This article describes a
conductive, stretchable composite consisting of a Cu-Ag
core-shell nanowire felt infiltrated with a silicone
elastomer. This composite exhibits a retention of
conductivity under strain that is superior to any composite
with a conductivity greater than 1000 S cm<sup>-1</sup>.
This work also shows how the mechanical properties,
conductivity, and deformation mechanism of the composite
changes as a function of the stiffness of the silicone
matrix. The retention of conductivity under strain was found
to decrease as the Young's modulus of the matrix increased.
This was attributed to void formation as a result of
debonding between the nanowire felt and the elastomer. The
nanowire composite was also patterned to create serpentine
circuits with a stretchability of 300%.},
Doi = {10.1021/acsnano.8b00887},
Key = {fds336319}
}
@article{fds330264,
Author = {Flowers, PF and Reyes, C and Ye, S and Kim, MJ and Wiley,
BJ},
Title = {3D printing electronic components and circuits with
conductive thermoplastic filament},
Journal = {Additive Manufacturing},
Volume = {18},
Pages = {156-163},
Publisher = {Elsevier BV},
Year = {2017},
Month = {December},
url = {http://dx.doi.org/10.1016/j.addma.2017.10.002},
Abstract = {This work examines the use of dual-material fused filament
fabrication for 3D printing electronic components and
circuits with conductive thermoplastic filaments. The
resistivity of traces printed from conductive thermoplastic
filaments made with carbon-black, graphene, and copper as
conductive fillers was found to be 12, 0.78, and 0.014 Ω
cm, respectively, enabling the creation of resistors with
values spanning 3 orders of magnitude. The carbon black and
graphene filaments were brittle and fractured easily, but
the copper-based filament could be bent at least 500 times
with little change in its resistance. Impedance measurements
made on the thermoplastic filaments demonstrate that the
copper-based filament had an impedance similar to a copper
PCB trace at frequencies greater than 1 MHz. Dual material
3D printing was used to fabricate a variety of inductors and
capacitors with properties that could be predictably tuned
by modifying either the geometry of the components, or the
materials used to fabricate the components. These resistors,
capacitors, and inductors were combined to create a fully 3D
printed high-pass filter with properties comparable to its
conventional counterparts. The relatively low impedance of
the copper-based filament enabled its use for 3D printing of
a receiver coil for wireless power transfer. We also
demonstrate the ability to embed and connect surface mounted
components in 3D printed objects with a low-cost ($1000 in
parts), open source dual-material 3D printer. This work thus
demonstrates the potential for FFF 3D printing to create
complex, three-dimensional circuits composed of either
embedded or fully-printed electronic components.},
Doi = {10.1016/j.addma.2017.10.002},
Key = {fds330264}
}
@article{fds325595,
Author = {Catenacci, MJ and Flowers, PF and Cao, C and Andrews, JB and Franklin,
AD and Wiley, BJ},
Title = {Fully Printed Memristors from Cu–SiO2
Core–Shell Nanowire Composites},
Journal = {Journal of Electronic Materials},
Volume = {46},
Number = {7},
Pages = {4596-4603},
Publisher = {Springer Nature},
Year = {2017},
Month = {July},
url = {http://dx.doi.org/10.1007/s11664-017-5445-5},
Abstract = {This article describes a fully printed memory in which a
composite of Cu–SiO2 nanowires dispersed in ethylcellulose
acts as a resistive switch between printed Cu and Au
electrodes. A 16-cell crossbar array of these memristors was
printed with an aerosol jet. The memristors exhibited
moderate operating voltages (∼3 V), no degradation over
104 switching cycles, write speeds of 3 μs, and
extrapolated retention times of 10 years. The low operating
voltage enabled the programming of a fully printed 4-bit
memristor array with an Arduino. The excellent performance
of these fully printed memristors could help enable the
creation of fully printed RFID tags and sensors with
integrated data storage.},
Doi = {10.1007/s11664-017-5445-5},
Key = {fds325595}
}
@article{fds326313,
Author = {Xie, Y and Ye, S and Reyes, C and Sithikong, P and Popa, BI and Wiley, BJ and Cummer, SA},
Title = {Microwave metamaterials made by fused deposition 3D printing
of a highly conductive copper-based filament},
Journal = {Applied Physics Letters},
Volume = {110},
Number = {18},
Pages = {181903-181903},
Publisher = {AIP Publishing},
Year = {2017},
Month = {May},
url = {http://dx.doi.org/10.1063/1.4982718},
Abstract = {This work reports a method for fabricating three-dimensional
microwave metamaterials by fused deposition modeling 3D
printing of a highly conductive polymer composite filament.
The conductivity of such a filament is shown to be nearly
equivalent to that of a perfect conductor for microwave
metamaterial applications. The expanded degrees-of-freedom
made available by 3D metamaterial designs are demonstrated
by designing, fabricating, and testing a 3D-printed unit
cell with a broadband permittivity as high as 14.4. The
measured and simulated S-parameters agree well with a mean
squared error smaller than 0.1. The presented method not
only allows reliable and convenient fabrication of microwave
metamaterials with high conductivity but also opens the door
to exploiting the third dimension of the unit cell design
space to achieve enhanced electromagnetic
properties.},
Doi = {10.1063/1.4982718},
Key = {fds326313}
}
@article{fds326817,
Author = {Yang, F and Tadepalli, V and Wiley, BJ},
Title = {3D Printing of a Double Network Hydrogel with a Compression
Strength and Elastic Modulus Greater than those of
Cartilage.},
Journal = {ACS biomaterials science & engineering},
Volume = {3},
Number = {5},
Pages = {863-869},
Publisher = {American Chemical Society (ACS)},
Year = {2017},
Month = {May},
url = {http://dx.doi.org/10.1021/acsbiomaterials.7b00094},
Abstract = {This article demonstrates a two-step method to 3D print
double network hydrogels at room temperature with a low-cost
($300) 3D printer. A first network precursor solution was
made 3D printable via extrusion from a nozzle by adding a
layered silicate to make it shear-thinning. After printing
and UV-curing, objects were soaked in a second network
precursor solution and UV-cured again to create
interpenetrating networks of poly(2-acrylamido-2-methylpropanesulfonate)
and polyacrylamide. By varying the ratio of polyacrylamide
to cross-linker, the trade-off between stiffness and maximum
elongation of the gel can be tuned to yield a compression
strength and elastic modulus of 61.9 and 0.44 MPa,
respectively, values that are greater than those reported
for bovine cartilage. The maximum compressive (93.5 MPa) and
tensile (1.4 MPa) strengths of the gel are twice that of
previous 3D printed gels, and the gel does not deform after
it is soaked in water. By 3D printing a synthetic meniscus
from an X-ray computed tomography image of an anatomical
model, we demonstrate the potential to customize hydrogel
implants based on 3D images of a patient's
anatomy.},
Doi = {10.1021/acsbiomaterials.7b00094},
Key = {fds326817}
}
@article{fds330265,
Author = {Stewart, IE and Kim, MJ and Wiley, BJ},
Title = {Effect of Morphology on the Electrical Resistivity of Silver
Nanostructure Films.},
Journal = {ACS applied materials & interfaces},
Volume = {9},
Number = {2},
Pages = {1870-1876},
Year = {2017},
Month = {January},
url = {http://dx.doi.org/10.1021/acsami.6b12289},
Abstract = {The relatively high temperatures (>200 °C) required to
sinter silver nanoparticle inks have limited the development
of printed electronic devices on low-cost, heat-sensitive
paper and plastic substrates. This article explores the
change in morphology and resistivity that occurs upon
heating thick films of silver nanowires (of two different
lengths; Ag NWs), nanoparticles (Ag NPs), and microflakes
(Ag MFs) at temperatures between 70 and 400 °C. After
heating at 70 °C, films of long Ag NWs exhibited a
resistivity of 1.8 × 10<sup>-5</sup> Ω cm, 4000 times more
conductive than films made from Ag NPs. This result
indicates the resistivity of thick films of silver
nanostructures is dominated by the contact resistance
between particles before sintering. After sintering at 300
°C, the resistivity of short Ag NWs, long Ag NWs, and Ag
NPs converge to a value of (2-3) × 10<sup>-5</sup> Ω cm,
while films of Ag MFs remain ∼10× less conductive (4.06
× 10<sup>-4</sup> Ω cm). Thus, films of long Ag NW films
heated at 70 °C are more conductive than Ag NP films
sintered at 300 °C. Adding 10 wt % nanowires to a film of
nanoparticles results in a 400-fold improvement in
resistivity.},
Doi = {10.1021/acsami.6b12289},
Key = {fds330265}
}
@article{fds326594,
Author = {Kim, MJ and Flowers, PF and Stewart, IE and Ye, S and Baek, S and Kim, JJ and Wiley, BJ},
Title = {Ethylenediamine Promotes Cu Nanowire Growth by Inhibiting
Oxidation of Cu(111).},
Journal = {Journal of the American Chemical Society},
Volume = {139},
Number = {1},
Pages = {277-284},
Year = {2017},
Month = {January},
url = {http://dx.doi.org/10.1021/jacs.6b10653},
Abstract = {The synthesis of metal nanostructures usually requires a
capping agent that is generally thought to cause anisotropic
growth by blocking the addition of atoms to specific crystal
facets. This work uses a series of electrochemical
measurements with a quartz crystal microbalance and
single-crystal electrodes to elucidate the facet-selective
chemistry occurring in the synthesis of Cu nanowires.
Contrary to prevailing hypotheses, ethylenediamine, a
so-called capping agent in the synthesis of Cu nanowires,
causes anisotropic growth by increasing the rate of atomic
addition to (111) facets at the end of a growing nanowire
relative to (100) facets on the sides of a nanowire.
Ethylenediamine increases the reduction rate of
Cu(OH)<sub>2</sub><sup>-</sup> on a Cu(111) surface relative
to Cu(100) by selectively inhibiting the formation of Cu
oxide on Cu(111). This work demonstrates how studying
facet-selective electrochemistry can improve the
understanding of the processes by which atoms assemble to
form anisotropic metal nanostructures.},
Doi = {10.1021/jacs.6b10653},
Key = {fds326594}
}
@article{fds333192,
Author = {Flowers, PF and Catenacci, MJ and Wiley, BJ},
Title = {High-speed, solution-coatable memory based on
Cu-SiO2 core-shell nanowires.},
Journal = {Nanoscale horizons},
Volume = {1},
Number = {4},
Pages = {313-316},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2016},
Month = {July},
url = {http://dx.doi.org/10.1039/c6nh00020g},
Abstract = {Printable electronics has the potential to drastically
reduce the environmental and economic costs associated with
the production of electronic devices, as well as enable
rapid prototyping of circuits and their printing on demand,
similar to what 3D printing has done for structural objects.
A major barrier to the realization of printable computers
that can run programs is the lack of a solution-coatable
non-volatile memory with performance metrics comparable to
silicon-based devices. Here we demonstrate a non-volatile
memory based on Cu-SiO<sub>2</sub> core-shell nanowires that
can be printed from solution and exhibits on-off ratios of
10<sup>6</sup>, switching speeds of 50 ns, a low operating
voltage of 2 V, and operates for at least 10<sup>4</sup>
cycles without failure. Each of these metrics is similar to
or better than Flash memory (the write speed is 20 times
faster than Flash). Memory architectures based on the
individual memory cells demonstrated here could enable the
printing of the more complex, embedded computing devices
that are expected to make up an internet of
things.},
Doi = {10.1039/c6nh00020g},
Key = {fds333192}
}
@article{fds322360,
Author = {Zhang, J and Wang, Q and Zhang, X and Wang, J and Guo, M and Wiley, BJ and Li,
C and Hu, C},
Title = {Carbamide promoted polyol synthesis and transmittance
properties of silver nanocubes},
Journal = {Inorganic Chemistry Frontiers},
Volume = {3},
Number = {4},
Pages = {547-555},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2016},
Month = {April},
url = {http://dx.doi.org/10.1039/c5qi00256g},
Abstract = {In this work, silver (Ag) nanocubes with different sizes
were rapidly synthesized with a modified HCl-based polyol
approach by employing carbamide (CO(NH2)2) as the additive
or promoter, which could shorten the reaction time from
about 25 h to less than 4 h and the method could be
confirmed as facile and robust. In the reaction system, the
NH3 molecules play the role of aggregating Ag+ and
[Ag(NH3)2]+ could gradually release Ag+, which in turn
results in formation of a more homogeneous product in a
short time (50 min-4 h). Some factors affecting the
synthesis including the concentration, reaction time and
agitator speed have also been investigated, which could be
adjusted to control the size, morphology, purity and
uniformity of the Ag nanocubes. A mechanism for the rapid
synthesis of the Ag nanocubes was proposed. To overcome the
lower repeatability of reported methods, we have supplied a
robust method to synthesize Ag nanocubes and this procedure
may provide a useful guide for the future synthesis of Ag or
other metal nanoparticles. The transmittance properties of
the different Ag nanocubes have also been detected, which
demonstrated that the transmittance of the Au film coupled
with the Ag nanocubes is very sensitive to not only the size
of the Ag nanocubes but also the thickness of the
polyelectrolyte molecular spacer layers.},
Doi = {10.1039/c5qi00256g},
Key = {fds322360}
}
@article{fds322359,
Author = {Ye, S and Stewart, IE and Chen, Z and Li, B and Rathmell, AR and Wiley,
BJ},
Title = {How Copper Nanowires Grow and How To Control Their
Properties.},
Journal = {Accounts of chemical research},
Volume = {49},
Number = {3},
Pages = {442-451},
Year = {2016},
Month = {March},
url = {http://dx.doi.org/10.1021/acs.accounts.5b00506},
Abstract = {Scalable, solution-phase nanostructure synthesis has the
promise to produce a wide variety of nanomaterials with
novel properties at a cost that is low enough for these
materials to be used to solve problems. For example,
solution-synthesized metal nanowires are now being used to
make low cost, flexible transparent electrodes in touch
screens, organic light-emitting diodes (OLEDs), and solar
cells. There has been a tremendous increase in the number of
solution-phase syntheses that enable control over the
assembly of atoms into nanowires in the last 15 years, but
proposed mechanisms for nanowire formation are usually
qualitative, and for many syntheses there is little
consensus as to how nanowires form. It is often not clear
what species is adding to a nanowire growing in solution or
what mechanistic step limits its rate of growth. A deeper
understanding of nanowire growth is important for
efficiently directing the development of nanowire synthesis
toward producing a wide variety of nanostructure
morphologies for structure-property studies or producing
precisely defined nanostructures for a specific application.
This Account reviews our progress over the last five years
toward understanding how copper nanowires form in solution,
how to direct their growth into nanowires with dimensions
ideally suited for use in transparent conducting films, and
how to use copper nanowires as a template to grow core-shell
nanowires. The key advance enabling a better understanding
of copper nanowire growth is the first real-time
visualization of nanowire growth in solution, enabling the
acquisition of nanowire growth kinetics. By measuring the
growth rate of individual nanowires as a function of
concentration of the reactants and temperature, we show that
a growing copper nanowire can be thought of as a
microelectrode that is charged with electrons by hydrazine
and grows through the diffusion-limited addition of
Cu(OH)2(-). This deeper mechanistic understanding, coupled
to an understanding of the structure-property relationship
of nanowires in transparent conducting films, enabled the
production of copper nanowires that can be coated from
solution to make films with properties that rival the
dominant transparent conductor, indium tin oxide. Finally,
we show how copper nanowires can be coated with Zn, Sn, In,
Ni, Co, Ag, Au, and Pt to protect them from oxidation or
enable their use as transparent electrocatalysts.},
Doi = {10.1021/acs.accounts.5b00506},
Key = {fds322359}
}
@article{fds330266,
Author = {Stewart, IE and Ye, S and Chen, Z and Flowers, PF and Wiley,
BJ},
Title = {Synthesis of Cu-Ag, Cu-Au, and Cu-Pt Core-Shell Nanowires
and Their Use in Transparent Conducting Films},
Journal = {Chemistry of Materials},
Volume = {27},
Number = {22},
Pages = {7788-7794},
Publisher = {American Chemical Society (ACS)},
Year = {2015},
Month = {November},
url = {http://dx.doi.org/10.1021/acs.chemmater.5b03709},
Abstract = {This article describes a room-temperature solution-phase
process for the synthesis of copper-silver (Cu-Ag),
copper-gold (Cu-Au), and copper-platinum (Cu-Pt) core-shell
nanowires (NWs) in which ascorbic acid removes the
passivating copper oxide coating from the Cu NWs and reduces
noble metal ions onto the Cu NWs while preventing galvanic
replacement. Cu-Ag NWs are conductive as printed, and the
resulting NW films exhibit optoelectronic properties
equivalent to films of Ag NWs with a similar aspect ratio.
Unlike Cu NWs, Cu-Ag NWs were resistant to oxidation in dry
air at 160°C and under humid conditions (85% RH) at 85°C
for 24 h.},
Doi = {10.1021/acs.chemmater.5b03709},
Key = {fds330266}
}
@article{fds322361,
Author = {Prasai, B and Wilson, AR and Wiley, BJ and Ren, Y and Petkov,
V},
Title = {On the road to metallic nanoparticles by rational design:
bridging the gap between atomic-level theoretical modeling
and reality by total scattering experiments.},
Journal = {Nanoscale},
Volume = {7},
Number = {42},
Pages = {17902-17922},
Year = {2015},
Month = {November},
url = {http://dx.doi.org/10.1039/c5nr04678e},
Abstract = {The extent to which current theoretical modeling alone can
reveal real-world metallic nanoparticles (NPs) at the atomic
level was scrutinized and demonstrated to be insufficient
and how it can be improved by using a pragmatic approach
involving straightforward experiments is shown. In
particular, 4 to 6 nm in size silica supported
Au(100-x)Pd(x) (x = 30, 46 and 58) explored for catalytic
applications is characterized structurally by total
scattering experiments including high-energy synchrotron
X-ray diffraction (XRD) coupled to atomic pair distribution
function (PDF) analysis. Atomic-level models for the NPs are
built by molecular dynamics simulations based on the
archetypal for current theoretical modeling Sutton-Chen (SC)
method. Models are matched against independent experimental
data and are demonstrated to be inaccurate unless their
theoretical foundation, i.e. the SC method, is supplemented
with basic yet crucial information on the length and
strength of metal-to-metal bonds and, when necessary,
structural disorder in the actual NPs studied. An atomic
PDF-based approach for accessing such information and
implementing it in theoretical modeling is put forward. For
completeness, the approach is concisely demonstrated on 15
nm in size water-dispersed Au particles explored for
bio-medical applications and 16 nm in size hexane-dispersed
Fe48Pd52 particles explored for magnetic applications as
well. It is argued that when "tuned up" against experiments
relevant to metals and alloys confined to nanoscale
dimensions, such as total scattering coupled to atomic PDF
analysis, rather than by mere intuition and/or against data
for the respective solids, atomic-level theoretical modeling
can provide a sound understanding of the
synthesis-structure-property relationships in real-world
metallic NPs. Ultimately this can help advance nanoscience
and technology a step closer to producing metallic NPs by
rational design.},
Doi = {10.1039/c5nr04678e},
Key = {fds322361}
}
@article{fds290772,
Author = {Li, B and Ye, S and Stewart, IE and Alvarez, S and Wiley,
BJ},
Title = {Synthesis and Purification of Silver Nanowires To Make
Conducting Films with a Transmittance of
99%.},
Journal = {Nano letters},
Volume = {15},
Number = {10},
Pages = {6722-6726},
Year = {2015},
Month = {October},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/acs.nanolett.5b02582},
Abstract = {Metal nanowire (NW) networks have the highest performance of
any solution-coatable alternative to ITO, but there is as
yet no published process for producing NW films with
optoelectronic performance that exceeds that of ITO. Here,
we demonstrate a process for the synthesis and purification
of Ag NWs that, when coated from an ink to create a
transparent conducting film, exhibit properties that exceed
that of ITO. The diameter, and thus optoelectronic
performance, of Ag NWs produced by a polyol synthesis can be
controlled by adjusting the concentration of bromide. Ag NWs
with diameters of 20 nm and aspect ratios up to 2000 were
obtained by adding 2.2 mM NaBr to a Ag NW synthesis, but
these NWs were contaminated by nanoparticles. Selective
precipitation was used to purify the NWs, resulting in a
transmittance improvement as large as 4%. At 130.0 Ω
sq(-1), the transmittance of the purified Ag NW film was
99.1%.},
Doi = {10.1021/acs.nanolett.5b02582},
Key = {fds290772}
}
@article{fds234760,
Author = {Borchert, JW and Stewart, IE and Ye, S and Rathmell, AR and Wiley, BJ and Winey, KI},
Title = {Effects of length dispersity and film fabrication on the
sheet resistance of copper nanowire transparent
conductors.},
Journal = {Nanoscale},
Volume = {7},
Number = {34},
Pages = {14496-14504},
Year = {2015},
Month = {September},
ISSN = {2040-3364},
url = {http://dx.doi.org/10.1039/c5nr03671b},
Abstract = {Development of thin-film transparent conductors (TC) based
on percolating networks of metal nanowires has leaped
forward in recent years, owing to the improvement of
nanowire synthetic methods and modeling efforts by several
research groups. While silver nanowires are the first
commercially viable iteration of this technology, systems
based on copper nanowires are not far behind. Here we
present an analysis of TCs composed of copper nanowire
networks on sheets of polyethylene terephthalate that have
been treated with various oxide-removing post treatments to
improve conductivity. A pseudo-2D rod network modeling
approach has been modified to include lognormal
distributions in length that more closely reflect
experimental data collected from the nanowire TCs. In our
analysis, we find that the copper nanowire TCs are capable
of achieving comparable electrical performance to silver
nanowire TCs with similar dimensions. Lastly, we present a
method for more accurately determining the nanowire area
coverage in a TC over a large area using Rutherford
Backscattering Spectrometry (RBS) to directly measure the
metal content in the TCs. These developments will aid
research and industry groups alike in the characterization
of nanowire based TCs.},
Doi = {10.1039/c5nr03671b},
Key = {fds234760}
}
@article{fds234761,
Author = {Yang, Y and Pham, AT and Cruz, D and Reyes, C and Wiley, BJ and Lopez, GP and Yellen, BB},
Title = {Assembly of colloidal molecules, polymers, and crystals in
acoustic and magnetic fields.},
Journal = {Advanced materials (Deerfield Beach, Fla.)},
Volume = {27},
Number = {32},
Pages = {4725-4731},
Year = {2015},
Month = {August},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.201500462},
Abstract = {A dynamically adjustable colloidal assembly technique is
presented, which combines magnetic and acoustic fields to
produce a wide range of colloidal structures, ranging from
discrete colloidal molecules, to polymer networks and
crystals. The structures can be stabilized and dried, making
them suitable for the fabrication of advanced
materials.},
Doi = {10.1002/adma.201500462},
Key = {fds234761}
}
@article{fds234763,
Author = {Du, J and Chen, Z and Ye, S and Wiley, BJ and Meyer,
TJ},
Title = {Copper as a robust and transparent electrocatalyst for water
oxidation.},
Journal = {Angewandte Chemie (International ed. in English)},
Volume = {54},
Number = {7},
Pages = {2073-2078},
Year = {2015},
Month = {February},
ISSN = {1433-7851},
url = {http://dx.doi.org/10.1002/anie.201408854},
Abstract = {Copper metal is in theory a viable oxidative electrocatalyst
based on surface oxidation to Cu(III) and/or Cu(IV) , but
its use in water oxidation has been impeded by anodic
corrosion. The in situ formation of an efficient
interfacial oxygen-evolving Cu catalyst from Cu(II) in
concentrated carbonate solutions is presented. The catalyst
necessitates use of dissolved Cu(II) and accesses the higher
oxidation states prior to decompostion to form an active
surface film, which is limited by solution conditions. This
observation and restriction led to the exploration of ways
to use surface-protected Cu metal as a robust
electrocatalyst for water oxidation. Formation of a compact
film of CuO on Cu surface prevents anodic corrosion and
results in sustained catalytic water oxidation. The Cu/CuO
surface stabilization was also applied to Cu nanowire films,
which are transparent and flexible electrocatalysts for
water oxidation and are an attractive alternative to
ITO-supported catalysts for photoelectrochemical
applications.},
Doi = {10.1002/anie.201408854},
Key = {fds234763}
}
@article{fds234764,
Author = {Alvarez, S and Ye, S and Flowers, PF and Wiley, BJ},
Title = {Photocatalytic growth of copper nanowires from
Cu2O seeds},
Journal = {Chemistry of Materials},
Volume = {27},
Number = {2},
Pages = {570-573},
Publisher = {American Chemical Society (ACS)},
Year = {2015},
Month = {January},
ISSN = {0897-4756},
url = {http://dx.doi.org/10.1021/cm504026w},
Abstract = {This article describes the photocatalytic growth of copper
nanowires from Cu2O octahedra. When exposed to visible light
with an energy greater than the band gap of Cu2O, electrons
excited from the valence band to the conduction band within
Cu2O octahedra reduce Cu(OH)2- onto the octahedra to form
copper nanowires. This phenomenon was used to turn nanowire
growth on and off with visible light, as well as pattern the
growth of nanowires on a substrate.},
Doi = {10.1021/cm504026w},
Key = {fds234764}
}
@article{fds234766,
Author = {Ye, S and Rathmell, AR and Chen, Z and Stewart, IE and Wiley,
BJ},
Title = {Metal nanowire networks: the next generation of transparent
conductors.},
Journal = {Advanced materials (Deerfield Beach, Fla.)},
Volume = {26},
Number = {39},
Pages = {6670-6687},
Year = {2014},
Month = {October},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.201402710},
Abstract = {There is an ongoing drive to replace the most common
transparent conductor, indium tin oxide (ITO), with a
material that gives comparable performance, but can be
coated from solution at speeds orders of magnitude faster
than the sputtering processes used to deposit ITO. Metal
nanowires are currently the only alternative to ITO that
meets these requirements. This Progress Report summarizes
recent advances toward understanding the relationship
between the structure of metal nanowires, the electrical and
optical properties of metal nanowires, and the properties of
a network of metal nanowires. Using the structure-property
relationship of metal nanowire networks as a roadmap, this
Progress Report describes different synthetic strategies to
produce metal nanowires with the desired properties.
Practical aspects of processing metal nanowires into
high-performance transparent conducting films are discussed,
as well as the use of nanowire films in a variety of
applications.},
Doi = {10.1002/adma.201402710},
Key = {fds234766}
}
@article{fds234765,
Author = {Chen, Z and Ye, S and Stewart, IE and Wiley, BJ},
Title = {Copper nanowire networks with transparent oxide shells that
prevent oxidation without reducing transmittance.},
Journal = {ACS nano},
Volume = {8},
Number = {9},
Pages = {9673-9679},
Year = {2014},
Month = {September},
ISSN = {1936-0851},
url = {http://dx.doi.org/10.1021/nn504308n},
Abstract = {Transparent conducting films of solution-synthesized copper
nanowires are an attractive alternative to indium tin oxide
due to the relative abundance of Cu and the low cost of
solution-phase nanowire coating processes. However, there
has to date been no way to protect Cu nanowires with a
solution-phase process that does not adversely affect the
optoelectric performance of Cu nanowire films. This article
reports that the electrodeposition of zinc, tin, or indium
shells onto Cu nanowires, followed by oxidation of these
shells, enables the protection of Cu nanowire films against
oxidation without decreasing film performance.},
Doi = {10.1021/nn504308n},
Key = {fds234765}
}
@article{fds234767,
Author = {Long, R and Zhou, S and Wiley, BJ and Xiong, Y},
Title = {Oxidative etching for controlled synthesis of metal
nanocrystals: atomic addition and subtraction.},
Journal = {Chemical Society reviews},
Volume = {43},
Number = {17},
Pages = {6288-6310},
Year = {2014},
Month = {September},
ISSN = {0306-0012},
url = {http://dx.doi.org/10.1039/c4cs00136b},
Abstract = {Since the discovery of the role of oxidative etching in
shape-controlled metal nanostructure synthesis in 2004, it
has become a versatile tool to precisely manipulate the
nucleation and growth of metal nanocrystals at the atomic
level. Subsequent research has shown that oxidative etching
can be used to reshape nanocrystals via atomic addition and
subtraction. This research has attracted extensive attention
from the community because of its promising practical
applications and theoretical value, and as a result,
tremendous efforts from numerous research groups have been
made to expand and apply this method to their own research.
In this review, we first outline the merits of oxidative
etching for the controlled synthesis of metal nanocrystals.
We then summarize recent progress in the use of oxidative
etching to control the morphology of a nanostructure during
and after its synthesis, and analyze its specific functions
in controlling a variety of nanocrystal parameters.
Applications enabled by oxidative etching are also briefly
presented to show its practical impact. Finally, we discuss
the challenges and opportunities for further development of
oxidative etching in nanocrystals synthesis.},
Doi = {10.1039/c4cs00136b},
Key = {fds234767}
}
@article{fds234768,
Author = {Ye, S and Chen, Z and Ha, Y-C and Wiley, BJ},
Title = {Real-time visualization of diffusion-controlled nanowire
growth in solution.},
Journal = {Nano letters},
Volume = {14},
Number = {8},
Pages = {4671-4676},
Year = {2014},
Month = {August},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl501762v},
Abstract = {This Letter shows that copper nanowires grow through the
diffusion-controlled reduction of dihydroxycopper(I),
Cu(OH)2(-). A combination of potentiostatic coulometry,
UV-visible spectroscopy, and thermodynamic calculations was
used to determine the species adding to growing Cu nanowires
is Cu(OH)2(-). Cyclic voltammetry was then used to measure
the diffusion coefficient of Cu(OH)2(-) in the reaction
solution. Given the diameter of a Cu nanowire and the
diffusion coefficient of Cu(OH)2(-), we calculated the
dependence of the diffusion-limited growth rate on the
concentration of copper ions to be 26 nm s(-1) mM(-1).
Independent measurements of the nanowire growth rate with
dark-field optical microscopy yielded 24 nm s(-1) mM(-1) for
the growth rate dependence on the concentration of copper.
Dependence of the nanowire growth rate on temperature
yielded a low activation energy of 11.5 kJ mol(-1),
consistent with diffusion-limited growth.},
Doi = {10.1021/nl501762v},
Key = {fds234768}
}
@article{fds234772,
Author = {Stewart, IE and Rathmell, AR and Yan, L and Ye, S and Flowers, PF and You,
W and Wiley, BJ},
Title = {Solution-processed copper-nickel nanowire anodes for organic
solar cells.},
Journal = {Nanoscale},
Volume = {6},
Number = {11},
Pages = {5980-5988},
Year = {2014},
Month = {June},
ISSN = {2040-3364},
url = {http://dx.doi.org/10.1039/c4nr01024h},
Abstract = {This work describes a process to make anodes for organic
solar cells from copper-nickel nanowires with solution-phase
processing. Copper nanowire films were coated from solution
onto glass and made conductive by dipping them in acetic
acid. Acetic acid removes the passivating oxide from the
surface of copper nanowires, thereby reducing the contact
resistance between nanowires to nearly the same extent as
hydrogen annealing. Films of copper nanowires were made as
oxidation resistant as silver nanowires under dry and humid
conditions by dipping them in an electroless nickel plating
solution. Organic solar cells utilizing these completely
solution-processed copper-nickel nanowire films exhibited
efficiencies of 4.9%.},
Doi = {10.1039/c4nr01024h},
Key = {fds234772}
}
@article{fds234774,
Author = {Ye, S and Rathmell, AR and Ha, Y-C and Wilson, AR and Wiley,
BJ},
Title = {The role of cuprous oxide seeds in the one-pot and seeded
syntheses of copper nanowires.},
Journal = {Small (Weinheim an der Bergstrasse, Germany)},
Volume = {10},
Number = {9},
Pages = {1771-1778},
Year = {2014},
Month = {May},
ISSN = {1613-6810},
url = {http://dx.doi.org/10.1002/smll.201303005},
Abstract = {This paper demonstrates that Cu2O nanoparticles form in the
early stages of a solution-phase synthesis of copper
nanowires, and aggregate to form the seeds from which copper
nanowires grow. Removal of ethylenediamine from the
synthesis leads to the rapid formation of Cu2O octahedra.
These octahedra are introduced as seeds in the same copper
nanowire synthesis to improve the yield of copper nanowires
from 12% to >55%, and to enable independent control over the
length of the nanowires. Transparent conducting films are
made from nanowires with different lengths to examine the
effect of nanowire aspect ratio on the film
performance.},
Doi = {10.1002/smll.201303005},
Key = {fds234774}
}
@article{fds234775,
Author = {Ye, S and Rathmell, AR and Stewart, IE and Ha, Y-C and Wilson, AR and Chen,
Z and Wiley, BJ},
Title = {A rapid synthesis of high aspect ratio copper nanowires for
high-performance transparent conducting films.},
Journal = {Chemical communications (Cambridge, England)},
Volume = {50},
Number = {20},
Pages = {2562-2564},
Year = {2014},
Month = {March},
url = {http://www.ncbi.nlm.nih.gov/pubmed/24346590},
Abstract = {This communication presents a way to produce copper
nanowires with aspect ratios as high as 5700 in 30 min, and
describes the growth processes responsible for their
formation. These nanowires were used to make transparent
conducting films with a transmittance >95% at a sheet
resistance <100 Ω sq(-1).},
Doi = {10.1039/c3cc48561g},
Key = {fds234775}
}
@article{fds234773,
Author = {Chen, Z and Ye, S and Wilson, AR and Ha, YC and Wiley,
BJ},
Title = {Optically transparent hydrogen evolution catalysts made from
networks of copper-platinum core-shell nanowires},
Journal = {Energy and Environmental Science},
Volume = {7},
Number = {4},
Pages = {1461-1467},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2014},
Month = {January},
ISSN = {1754-5692},
url = {http://dx.doi.org/10.1039/c4ee00211c},
Abstract = {This article reports the fabrication of copper-platinum
core-shell nanowires by electroplating platinum onto copper
nanowires, and the first demonstration of their use as a
transparent, conducting electrocatalyst for the hydrogen
evolution reaction (HER). Cu-Pt core-shell nanowire networks
exhibit mass activities up to 8 times higher than
carbon-supported Pt nanoparticles for the HER.
Electroplating minimizes galvanic replacement, allowing the
copper nanowires to retain their conductivity, and
eliminating the need for a conductive substrate or overcoat.
Cu-Pt core-shell nanowire networks can thus replace more
expensive transparent electrodes made from indium tin oxide
(ITO) in photoelectrolysis cells and dye sensitized solar
cells. Unlike ITO, Cu-Pt core-shell nanowire films retain
their conductivity after bending, retain their transmittance
during electrochemical reduction, and have consistently high
transmittance (>80%) across a wide optical window (300-1800
nm). This journal is © the Partner Organisations
2014.},
Doi = {10.1039/c4ee00211c},
Key = {fds234773}
}
@article{fds234778,
Author = {Chen, Z and Rathmell, AR and Ye, S and Wilson, AR and Wiley,
BJ},
Title = {Optically transparent water oxidation catalysts based on
copper nanowires.},
Journal = {Angewandte Chemie (International ed. in English)},
Volume = {52},
Number = {51},
Pages = {13708-13711},
Year = {2013},
Month = {December},
url = {http://www.ncbi.nlm.nih.gov/pubmed/24136831},
Abstract = {Let the light shine through: A transparent film of copper
nanowires was transformed into an electrocatalyst for water
oxidation by electrodepostion of Ni or Co onto the surface
of the nanowires. These core-shell nanowire networks exhibit
electrocatalytic performance equivalent to metal oxide films
of similar composition, but are several times more
transparent.},
Doi = {10.1002/anie.201306585},
Key = {fds234778}
}
@article{fds234777,
Author = {Mutiso, RM and Sherrott, MC and Rathmell, AR and Wiley, BJ and Winey,
KI},
Title = {Integrating simulations and experiments to predict sheet
resistance and optical transmittance in nanowire films for
transparent conductors.},
Journal = {ACS nano},
Volume = {7},
Number = {9},
Pages = {7654-7663},
Year = {2013},
Month = {September},
ISSN = {1936-0851},
url = {http://dx.doi.org/10.1021/nn403324t},
Abstract = {Metal nanowire films are among the most promising
alternatives for next-generation flexible,
solution-processed transparent conductors. Breakthroughs in
nanowire synthesis and processing have reported low sheet
resistance (Rs ≤ 100 Ω/sq) and high optical transparency
(%T > 90%). Comparing the merits of the various nanowires
and fabrication methods is inexact, because Rs and %T depend
on a variety of independent parameters including nanowire
length, nanowire diameter, areal density of the nanowires
and contact resistance between nanowires. In an effort to
account for these fundamental parameters of nanowire thin
films, this paper integrates simulations and experimental
results to build a quantitatively predictive model. First,
by fitting the results from simulations of quasi-2D rod
networks to experimental data from well-defined nanowire
films, we obtain an effective average contact resistance,
which is indicative of the nanowire chemistry and processing
methods. Second, this effective contact resistance is used
to simulate how the sheet resistance depends on the aspect
ratio (L/D) and areal density of monodisperse rods, as well
as the effect of mixtures of short and long nanowires on the
sheet resistance. Third, by combining our simulations of
sheet resistance and an empirical diameter-dependent
expression for the optical transmittance, we produced a
fully calculated plot of optical transmittance versus sheet
resistance. Our predictions for silver nanowires are
validated by experimental results for silver nanowire films,
where nanowires of L/D > 400 are required for high
performance transparent conductors. In contrast to a widely
used approach that employs a single percolative figure of
merit, our method integrates simulation and experimental
results to enable researchers to independently explore the
importance of contact resistance between nanowires, as well
as nanowire area fraction and arbitrary distributions in
nanowire sizes. To become competitive, metal nanowire
systems require a predictive tool to accelerate their design
and adoption for specific applications.},
Doi = {10.1021/nn403324t},
Key = {fds234777}
}
@article{fds234779,
Author = {Wilson, AR and Sun, K and Chi, M and White, RM and Lebeau, JM and Lamb, HH and Wiley, BJ},
Title = {From core-shell to alloys: The preparation and
characterization of solution-synthesized AuPd nanoparticle
catalysts},
Journal = {Journal of Physical Chemistry C},
Volume = {117},
Number = {34},
Pages = {17557-17566},
Publisher = {American Chemical Society (ACS)},
Year = {2013},
Month = {August},
ISSN = {1932-7447},
url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000323917300022&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92},
Abstract = {This article describes the solution-phase synthesis of 4 nm
gold nanoparticles with 0.7 atom-thick, 1.9 atom-thick, and
3.8 atom-thick layers of Pd on their surfaces. These
well-defined core-shell nanoparticles were deposited on a
silica support, calcined, and reduced at 300 C to create
alloyed nanoparticles containing 10.9, 20.2, and 28.5% Pd
(w/w). Monometallic Pd nanoparticles sintered during
calcination at 300 C, but no sintering was observed for AuPd
nanoparticles. Diffuse reflectance infrared Fourier
transform (DRIFT) spectra of adsorbed CO suggests that Au
donates d electron density to Pd in the core-shell and alloy
structures and confirms the presence of Au and Pd atoms on
the surface of the nanoparticles after calcination and
reduction. The properties of the AuPd alloy catalysts were
tested in the vapor-phase conversion of α-limonene to
p-cymene. AuPd nanoparticles containing 20% or more Pd per
particle produced p-cymene yields greater than 80%,
equivalent to conventional Pd catalysts prepared by
incipient wetness and ion exchange methods. Very low yields
of p-cymene were obtained from dehydrogenation of p-menthane
under equivalent conditions, suggesting that the production
of p-cymene from α-limonene proceeds through terpinene
intermediates. © 2013 American Chemical
Society.},
Doi = {10.1021/jp404157m},
Key = {fds234779}
}
@article{fds234780,
Author = {Wu, J and Zang, J and Rathmell, AR and Zhao, X and Wiley,
BJ},
Title = {Reversible sliding in networks of nanowires.},
Journal = {Nano letters},
Volume = {13},
Number = {6},
Pages = {2381-2386},
Year = {2013},
Month = {June},
url = {http://www.ncbi.nlm.nih.gov/pubmed/23634844},
Abstract = {This work demonstrates that metal nanowires in a percolating
network can reversibly slide across one another. Reversible
sliding allows networks of metal nanowires to maintain
electrical contact while being stretched to strains greater
than the fracture strain for individual nanowires. This
phenomenon was demonstrated by using networks of nanowires
as compliant electrodes for a dielectric elastomer actuator.
Reversible nanowire sliding enabled actuation to a maximum
area strain of 200% and repetitive cycling of the actuator
to an area strain of 25% over 150 times. During actuation,
the transmittance of the network increased 4.5 times, from
13% to 58%. Compared to carbon-based compliant electrodes,
networks of metal nanowires can actuate across a broader
range of optical transmittance. The widely tunable
transmittance of nanowire-based actuators allows for their
use as a light valve.},
Doi = {10.1021/nl4000739},
Key = {fds234780}
}
@article{fds234776,
Author = {Lassiter, JB and McGuire, F and Mock, JJ and Ciracì, C and Hill, RT and Wiley, BJ and Chilkoti, A and Smith, DR},
Title = {Plasmonic waveguide modes of film-coupled metallic
nanocubes.},
Journal = {Nano letters},
Volume = {13},
Number = {12},
Pages = {5866-5872},
Year = {2013},
Month = {January},
url = {http://www.ncbi.nlm.nih.gov/pubmed/24199752},
Abstract = {A metallic nanoparticle positioned over a metal film offers
great advantages as a highly controllable system relevant
for probing field-enhancement and other plasmonic effects.
Because the size and shape of the gap between the
nanoparticle and film can be controlled to subnanometer
precision using relatively simple, bottom-up fabrication
approaches, the film-coupled nanoparticle geometry has
recently been applied to enhancing optical fields, accessing
the quantum regime of plasmonics, and the design of surfaces
with controlled reflectance. In the present work, we examine
the plasmon modes associated with a silver nanocube
positioned above a silver or gold film, separated by an
organic, dielectric spacer layer. The film-coupled nanocube
is of particular interest due to the formation of waveguide
cavity-like modes between the nanocube and film. These modes
impart distinctive scattering characteristics to the system
that can be used in the creation of controlled reflectance
surfaces and other applications. We perform both
experimental spectroscopy and numerical simulations of
individual nanocubes positioned over a metal film, finding
excellent agreement between experiment and simulation. The
waveguide mode description serves as a starting point to
explain the optical properties observed.},
Doi = {10.1021/nl402660s},
Key = {fds234776}
}
@article{fds234799,
Author = {Moreau, A and Ciracì, C and Mock, JJ and Hill, RT and Wang, Q and Wiley,
BJ and Chilkoti, A and Smith, DR},
Title = {Controlled-reflectance surfaces with film-coupled colloidal
nanoantennas.},
Journal = {Nature},
Volume = {492},
Number = {7427},
Pages = {86-89},
Year = {2012},
Month = {December},
url = {http://www.ncbi.nlm.nih.gov/pubmed/23222613},
Abstract = {Efficient and tunable absorption is essential for a variety
of applications, such as designing controlled-emissivity
surfaces for thermophotovoltaic devices, tailoring an
infrared spectrum for controlled thermal dissipation and
producing detector elements for imaging. Metamaterials based
on metallic elements are particularly efficient as absorbing
media, because both the electrical and the magnetic
properties of a metamaterial can be tuned by structured
design. So far, metamaterial absorbers in the infrared or
visible range have been fabricated using lithographically
patterned metallic structures, making them inherently
difficult to produce over large areas and hence reducing
their applicability. Here we demonstrate a simple method to
create a metamaterial absorber by randomly adsorbing
chemically synthesized silver nanocubes onto a
nanoscale-thick polymer spacer layer on a gold film, making
no effort to control the spatial arrangement of the cubes on
the film. We show that the film-coupled nanocubes provide a
reflectance spectrum that can be tailored by varying the
geometry (the size of the cubes and/or the thickness of the
spacer). Each nanocube is the optical analogue of a grounded
patch antenna, with a nearly identical local field structure
that is modified by the plasmonic response of the metal's
dielectric function, and with an anomalously large
absorption efficiency that can be partly attributed to an
interferometric effect. The absorptivity of large surface
areas can be controlled using this method, at scales out of
reach of lithographic approaches (such as electron-beam
lithography) that are otherwise required to manipulate
matter on the nanoscale.},
Doi = {10.1038/nature11615},
Key = {fds234799}
}
@article{fds234797,
Author = {Rathmell, AR and Nguyen, M and Chi, M and Wiley, BJ},
Title = {Synthesis of oxidation-resistant cupronickel nanowires for
transparent conducting nanowire networks.},
Journal = {Nano letters},
Volume = {12},
Number = {6},
Pages = {3193-3199},
Year = {2012},
Month = {June},
url = {http://www.ncbi.nlm.nih.gov/pubmed/22642652},
Abstract = {Nanowires of copper can be coated from liquids to create
flexible, transparent conducting films that can potentially
replace the dominant transparent conductor, indium tin
oxide, in displays, solar cells, organic light-emitting
diodes, and electrochromic windows. One issue with these
nanowire films is that copper is prone to oxidation. It was
hypothesized that the resistance to oxidation could be
improved by coating copper nanowires with nickel. This work
demonstrates a method for synthesizing copper nanowires with
nickel shells as well as the properties of cupronickel
nanowires in transparent conducting films. Time- and
temperature-dependent sheet resistance measurements indicate
that the sheet resistance of copper and silver nanowire
films will double after 3 and 36 months at room temperature,
respectively. In contrast, the sheet resistance of
cupronickel nanowires containing 20 mol % nickel will double
in about 400 years. Coating copper nanowires to a ratio of
2:1 Cu:Ni gave them a neutral gray color, making them more
suitable for use in displays and electrochromic windows.
These properties, and the fact that copper and nickel are
1000 times more abundant than indium or silver, make
cupronickel nanowires a promising alternative for the
sustainable, efficient production of transparent
conductors.},
Doi = {10.1021/nl301168r},
Key = {fds234797}
}
@article{fds234796,
Author = {Zhu, Y and Qin, Q and Xu, F and Fan, F and Ding, Y and Zhang, T and Wiley, BJ and Wang, ZL},
Title = {Size effects on elasticity, yielding, and fracture of silver
nanowires: In situ experiments},
Journal = {Physical Review B - Condensed Matter and Materials
Physics},
Volume = {85},
Number = {4},
Publisher = {American Physical Society (APS)},
Year = {2012},
Month = {January},
ISSN = {1098-0121},
url = {http://dx.doi.org/10.1103/PhysRevB.85.045443},
Abstract = {This paper reports the quantitative measurement of a full
spectrum of mechanical properties of fivefold twinned silver
(Ag) nanowires (NWs), including Young's modulus, yield
strength, and ultimate tensile strength. In-situ tensile
testing of Ag NWs with diameters between 34 and 130 nm was
carried out inside a scanning electron microscope (SEM).
Young's modulus, yield strength, and ultimate tensile
strength all increased as the NW diameter decreased. The
maximum yield strength in our tests was found to be 2.64
GPa, which is about 50 times the bulk value and close to the
theoretical value of Ag in the 110 orientation. The size
effect in the yield strength is mainly due to the stiffening
size effect in the Young's modulus. Yield strain scales
reasonably well with the NW surface area, which reveals that
yielding of Ag NWs is due to dislocation nucleation from
surface sources. Pronounced strain hardening was observed
for most NWs in our study. The strain hardening, which has
not previously been reported for NWs, is mainly attributed
to the presence of internal twin boundaries. © 2012
American Physical Society.},
Doi = {10.1103/PhysRevB.85.045443},
Key = {fds234796}
}
@article{fds234798,
Author = {Khalil, KS and Sagastegui, A and Li, Y and Tahir, MA and Socolar, JES and Wiley, BJ and Yellen, BB},
Title = {Binary colloidal structures assembled through Ising
interactions},
Journal = {Nature Communications},
Volume = {3},
Pages = {794},
Year = {2012},
url = {http://www.ncbi.nlm.nih.gov/pubmed/22531179},
Abstract = {New methods for inducing microscopic particles to assemble
into useful macroscopic structures could open pathways for
fabricating complex materials that cannot be produced by
lithographic methods. Here we demonstrate a colloidal
assembly technique that uses two parameters to tune the
assembly of over 20 different pre-programmed structures,
including kagome, honeycomb and square lattices, as well as
various chain and ring configurations. We programme the
assembled structures by controlling the relative
concentrations and interaction strengths between spherical
magnetic and non-magnetic beads, which behave as
paramagnetic or diamagnetic dipoles when immersed in a
ferrofluid. A comparison of our experimental observations
with potential energy calculations suggests that the lowest
energy configuration within binary mixtures is determined
entirely by the relative dipole strengths and their relative
concentrations.},
Doi = {10.1038/ncomms1798},
Key = {fds234798}
}
@article{fds234800,
Author = {Bergin, SM and Rathmell, AR and Chen, YH and Charbonneau, P and Li, ZY and Wiley, BJ},
Title = {The effect of nanowire length and diameter on the properties
of transparent, conducting nanowire films},
Journal = {Nanoscale},
Volume = {4},
Number = {6},
Pages = {1996},
Year = {2012},
url = {http://www.ncbi.nlm.nih.gov/pubmed/22349106},
Abstract = {This article describes how the dimensions of nanowires
affect the transmittance and sheet resistance of a random
nanowire network. Silver nanowires with independently
controlled lengths and diameters were synthesized with a
gram-scale polyol synthesis by controlling the reaction
temperature and time. Characterization of films composed of
nanowires of different lengths but the same diameter enabled
the quantification of the effect of length on the
conductance and transmittance of silver nanowire films.
Finite-difference time-domain calculations were used to
determine the effect of nanowire diameter, overlap, and hole
size on the transmittance of a nanowire network. For
individual nanowires with diameters greater than 50 nm,
increasing diameter increases the electrical conductance to
optical extinction ratio, but the opposite is true for
nanowires with diameters less than this size. Calculations
and experimental data show that for a random network of
nanowires, decreasing nanowire diameter increases the number
density of nanowires at a given transmittance, leading to
improved connectivity and conductivity at high transmittance
(>90%). This information will facilitate the design of
transparent, conducting nanowire films for flexible
displays, organic light emitting diodes and thin-film solar
cells.},
Doi = {10.1039/C2NR30126A},
Key = {fds234800}
}
@article{fds234804,
Author = {Rathmell, AR and Wiley, BJ},
Title = {The synthesis and coating of long, thin copper nanowires to
make flexible, transparent conducting films on plastic
substrates.},
Journal = {Advanced materials (Deerfield Beach, Fla.)},
Volume = {23},
Number = {41},
Pages = {4798-4803},
Year = {2011},
Month = {November},
url = {http://www.ncbi.nlm.nih.gov/pubmed/21953576},
Doi = {10.1002/adma.201102284},
Key = {fds234804}
}
@article{fds234805,
Author = {Yang, L and Zhang, T and Zhou, H and Price, SC and Wiley, BJ and You,
W},
Title = {Solution-processed flexible polymer solar cells with silver
nanowire electrodes.},
Journal = {ACS applied materials & interfaces},
Volume = {3},
Number = {10},
Pages = {4075-4084},
Year = {2011},
Month = {October},
ISSN = {1944-8244},
url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000296128500040&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92},
Abstract = {The conventional anode for organic photovoltaics (OPVs),
indium tin oxide (ITO), is expensive and brittle, and thus
is not suitable for use in roll-to-roll manufacturing of
OPVs. In this study, fully solution-processed polymer bulk
heterojunction (BHJ) solar cells with anodes made from
silver nanowires (Ag NWs) have been successfully fabricated
with a configuration of Ag NWs/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)
(PEDOT:PSS)/polymer:phenyl-C(61)-butyric acid methyl ester
(PCBM)/Ca/Al. Efficiencies of 2.8 and 2.5% are obtained for
devices with Ag NW network on glass and on poly(ethylene
terephthalate) (PET), respectively. The efficiency of the
devices is limited by the low work function of the Ag
NWs/PEDOT:PSS film and the non-ideal ohmic contact between
the Ag NW anode and the active layer. Compared with devices
based on the ITO anode, the open-circuit voltage (V(oc)) of
solar cells based on the Ag NW anode is lower by ~0.3 V.
More importantly, highly flexible BHJ solar cells have been
firstly fabricated on Ag NWs/PET anode with recoverable
efficiency of 2.5% under large deformation up to 120°. This
study indicates that, with improved engineering of the
nanowires/polymer interface, Ag NW electrodes can serve as a
low-cost, flexible alternative to ITO, and thereby improve
the economic viability and mechanical stability of
OPVs.},
Doi = {10.1021/am2009585},
Key = {fds234805}
}
@article{fds234795,
Author = {Kubo, M and Li, X and Kim, C and Hashimoto, M and Wiley, BJ and Ham, D and Whitesides, GM},
Title = {Stretchable microfluidic electric circuit applied for radio
frequency antenna},
Journal = {Proceedings - Electronic Components and Technology
Conference},
Pages = {1582-1587},
Publisher = {IEEE},
Year = {2011},
Month = {July},
ISSN = {0569-5503},
url = {http://dx.doi.org/10.1109/ECTC.2011.5898722},
Abstract = {This paper describes a new method for fabricating highly
stretchable and robust electrical circuits. The circuits
consist of liquid metal (eutectic gallium indium alloy,
EGaIn) enclosed in elastomeric microfluidic channels. In
particular, a microfluidic hybrid structure made of two
types of elastomers (polydimethylsiloxane (PDMS) and Ecoflex
(type 0030, Reynolds Advanced Materials) with different
stiffness has been developed to improve the stretchability
and mechanical stability of the circuits. These circuits can
be flexed, twisted, and stretched up to 2.2 times of their
original length l 0. When we applied this stretchable
circuit for radio-frequency antennas, the antennas exhibited
no degradation in reflected power even after being
repeatedly stretched to l 1.50 l0 more than 100 times. This
stretchability also allows the resonance frequencies of the
antennas to be mechanically tuned around 1 GHz. The
stretchable and robust circuits may be useful in
reconfigurable and conformal structures, wearable sensors
and large-area electronics, and other devices that must
undergo large mechanical deformation. © 2011
IEEE.},
Doi = {10.1109/ECTC.2011.5898722},
Key = {fds234795}
}
@article{fds234802,
Author = {Yang, Y and Erb, RM and Wiley, BJ and Zauscher, S and Yellen,
BB},
Title = {Imaginary magnetic tweezers for massively parallel surface
adhesion spectroscopy.},
Journal = {Nano letters},
Volume = {11},
Number = {4},
Pages = {1681-1684},
Year = {2011},
Month = {April},
url = {http://www.ncbi.nlm.nih.gov/pubmed/21417363},
Abstract = {A massively parallel magnetic tweezer system has been
constructed that utilizes the self-repulsion of colloidal
beads from a planar interface via a magnetic dipole image
force. Self-repulsion enables the application of a uniform
magnetic force to thousands of beads simultaneously, which
permits the measurement of unbinding histograms at the
lowest loading rates ever tested. The adhesion of 9.8 μm
polystyrene beads to a fluorocarbon, PEG, and UV-irradiated
PEG surfaces were measured between 10(-3)-10(0) pN/s force
loading rates, revealing the presence of both kinetic and
quasi-equilibrium unbinding regimes.},
Doi = {10.1021/nl200189w},
Key = {fds234802}
}
@article{fds234801,
Author = {Xu, F and Durham, JW and Wiley, BJ and Zhu, Y},
Title = {Strain-release assembly of nanowires on stretchable
substrates.},
Journal = {ACS nano},
Volume = {5},
Number = {2},
Pages = {1556-1563},
Year = {2011},
Month = {February},
ISSN = {1936-0851},
url = {http://dx.doi.org/10.1021/nn103183d},
Abstract = {A simple yet effective method for assembly of highly aligned
nanowires (NWs) on stretchable substrates is reported. In
this method, NWs were first transferred to a strained
stretchable substrate. After the strain was released, the
NWs aligned in the transverse direction and the area
coverage of the NWs on the substrate increased. This method
can be applied to any NWs deposited on a stretchable film
and can be repeated multiple times to increase the alignment
and density of the NWs. For silver (Ag) and silicon (Si) NWs
on poly(dimethylsiloxane) (PDMS) substrates, the probability
of NW alignment increased from 29% to 90% for Ag NWs, and
from 25% to 88% for Si NWs after two assembly steps; the
density increased by 60% and 75% for the Ag and Si NWs,
respectively. The large-strain elasticity of the substrate
and the static friction between the NWs and the substrate
play key roles in this assembly method. We find that a model
that takes into account the volume incompressibility of PDMS
reliably predicts the degree of NW alignment and NW density.
The utility of this assembly method was demonstrated by
fabricating a strain sensor array composed of aligned Si NWs
on a PDMS substrate, with a device yield of
95%.},
Doi = {10.1021/nn103183d},
Key = {fds234801}
}
@article{fds234803,
Author = {Xu, J and Wilson, AR and Rathmell, AR and Howe, J and Chi, M and Wiley,
BJ},
Title = {Synthesis and Catalytic Properties of Au-Pd
Nanoflowers},
Journal = {ACS Nano},
Volume = {5},
Number = {5},
Pages = {6119-6127},
Year = {2011},
url = {http://www.ncbi.nlm.nih.gov/pubmed/21761821},
Abstract = {Reduction of Pd ions by hydroquinone in the presence of gold
nanoparticles and polyvinylpyrrolidone resulted in the
formation of nanoflowers with a Au core and Pd petals.
Addition of HCl to the synthesis halted the reduction by
hydroquinone and enabled the acquisition of snapshots of the
nanoflowers at different stages of growth. TEM images of the
reaction after 10 s show that the nanoflower morphology
resulted from the homogeneous nucleation of Pd clusters in
solution and their subsequent attachment to gold seeds
coated with a thin (0.8 ± 0.1 nm) shell of Pd. UV-visible
spectra also indicate Pd clusters formed in the early stages
of the reaction and disappeared as the nanoflowers grew. The
speed at which this reaction can be halted is useful not
only for producing a variety of bimetallic nanostructures
with precisely controlled dimensions and morphologies but
also for understanding the growth mechanism of these
structures. The ability of the AuPd core-shell structure to
catalyze the Suzuki coupling reaction of iodobenzene to
phenylboronic acid was probed and compared against the
activity of Pd nanocubes and thin-shelled AuPd core-shell
nanoparticles. The results of this study suggest that Suzuki
coupling was not affected by the surface structure or
subsurface composition of the nanoparticles, but instead was
primarily catalyzed by molecular Pd species that leached
from the nanostructures.},
Doi = {10.1021/nn201161m},
Key = {fds234803}
}
@article{fds234794,
Author = {Martinez, AW and Phillips, ST and Nie, Z and Cheng, CM and Carrilho, E and Wiley, BJ and Whitesides, GM},
Title = {Erratum: Programmable diagnostic devices made from paper and
tape (Lab on a Chip (2010) 10 (2499-2504) DOI:
10.1039/c0lc00021c)},
Journal = {Lab on a Chip},
Volume = {10},
Number = {24},
Pages = {3428},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2010},
Month = {December},
ISSN = {1473-0197},
url = {http://dx.doi.org/10.1039/C0LC90091E},
Doi = {10.1039/C0LC90091E},
Key = {fds234794}
}
@article{fds234792,
Author = {Martinez, AW and Phillips, ST and Nie, Z and Cheng, C-M and Carrilho, E and Wiley, BJ and Whitesides, GM},
Title = {Programmable diagnostic devices made from paper and
tape.},
Journal = {Lab on a chip},
Volume = {10},
Number = {19},
Pages = {2499-2504},
Year = {2010},
Month = {October},
ISSN = {1473-0197},
url = {http://dx.doi.org/10.1039/c0lc00021c},
Abstract = {This paper describes three-dimensional microfluidic
paper-based analytical devices (3-D microPADs) that can be
programmed (postfabrication) by the user to generate
multiple patterns of flow through them. These devices are
programmed by pressing single-use 'on' buttons, using a
stylus or a ballpoint pen. Pressing a button closes a small
space (gap) between two vertically aligned microfluidic
channels, and allows fluids to wick from one channel to the
other. These devices are simple to fabricate, and are made
entirely out of paper and double-sided adhesive tape.
Programmable devices expand the capabilities of microPADs
and provide a simple method for controlling the movement of
fluids in paper-based channels. They are the conceptual
equivalent of field-programmable gate arrays (FPGAs) widely
used in electronics.},
Doi = {10.1039/c0lc00021c},
Key = {fds234792}
}
@article{fds234793,
Author = {Rathmell, AR and Bergin, SM and Hua, Y-L and Li, Z-Y and Wiley,
BJ},
Title = {The growth mechanism of copper nanowires and their
properties in flexible, transparent conducting
films.},
Journal = {Advanced materials (Deerfield Beach, Fla.)},
Volume = {22},
Number = {32},
Pages = {3558-3563},
Year = {2010},
Month = {August},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20512817},
Abstract = {"Figure Presented" Copper nanowires grow from spherical
copper seeds in an aqueous solution. Conductive films of
copper nanowires have a transmittance of 65% (-15 % more
than the best values reported for carbon nanotubes), and
remain conductive after 1000 bending cycles or one month in
air. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA,
Weinheim.},
Doi = {10.1002/adma.201000775},
Key = {fds234793}
}
@article{fds234790,
Author = {Kubo, M and Li, X and Kim, C and Hashimoto, M and Wiley, BJ and Ham, D and Whitesides, GM},
Title = {Stretchable microfluidic radiofrequency antennas.},
Journal = {Advanced materials (Deerfield Beach, Fla.)},
Volume = {22},
Number = {25},
Pages = {2749-2752},
Year = {2010},
Month = {July},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.200904201},
Abstract = {(Figure Presented) Highly stretchable and robust antennas
are fabricated by injecting liquid metal into a microfluidic
channel that consists of two types of silicone rubber with
different stiffness. The resulting antennas exhibit high
mechanical stability under strain, while retaining high
stretchability; these antennas can be stretched by up to a
tensile strain of 120 % with little degradation in radiation
efficiency. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA,
Weinheim.},
Doi = {10.1002/adma.200904201},
Key = {fds234790}
}
@article{fds234791,
Author = {Wiley, BJ and Qin, D and Xia, Y},
Title = {Nanofabrication at high throughput and low
cost.},
Journal = {ACS nano},
Volume = {4},
Number = {7},
Pages = {3554-3559},
Year = {2010},
Month = {July},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20695512},
Abstract = {The task of nanofabrication can, in principle, be divided
into two separate tracks: generation and replication of the
patterned features. These two tracks are different in terms
of characteristics, requirements, and aspects of emphasis.
In general, generation of patterns is commonly achieved in a
serial fashion using techniques that are typically slow,
making this process only practical for making a small number
of copies. Only when combined with a rapid duplication
technique will fabrication at high-throughput and low-cost
become feasible. Nanoskiving is unique in that it can be
used for both generation and duplication of patterned
nanostructures.},
Doi = {10.1021/nn101472p},
Key = {fds234791}
}
@article{fds234807,
Author = {Lipomi, DJ and Ilievski, F and Wiley, BJ and Deotare, PB and Loncar, M and Whitesides, GM},
Title = {Integrated fabrication and magnetic positioning of metallic
and polymeric nanowires embedded in thin epoxy
slabs.},
Journal = {ACS nano},
Volume = {3},
Number = {10},
Pages = {3315-3325},
Year = {2009},
Month = {October},
ISSN = {1936-0851},
url = {http://dx.doi.org/10.1021/nn901002q},
Abstract = {This paper describes a process for the fabrication and
positioning of nanowires (of Au, Pd, and conjugated
polymers) embedded in thin epoxy slabs. The procedure has
four steps: (i) coembedding a thin film of metal or
conducting polymer with a thin film of nickel metal (Ni) in
epoxy; (ii) sectioning the embedded structures into
nanowires with an ultramicrotome ("nanoskiving"); (iii)
floating the epoxy sections on a pool of water; and (iv)
positioning the sections with an external magnet to a
desired location ("magnetic mooring"). As the water
evaporates, capillary interactions cause the sections to
adhere to the substrate. Both the Ni and epoxy can be etched
to generate free-standing metallic nanowires. The average
translational deviation in the positioning of two nanowires
with respect to each other is 16 +/- 13 mum, and the average
angular deviation is 3 +/- 2 degrees . Successive
depositions of nanowires yield the following structures of
interest for electronic and photonic applications:
electrically continuous junctions of two Au nanowires, two
Au nanowires spanned by a poly(3-hexylthiophene) (P3HT)
nanowire; single-crystalline Au nanowires that cross;
crossbar arrays of Au nanowires; crossbar arrays of Au and
Pd nanowires; and a 50 x 50 array of poly(benzimidazobenzophenanthroline
ladder) (BBL) nanowires. Single-crystalline Au nanowires can
be placed on glass wool fibers or on microfabricated
polymeric waveguides, with which the nanowire can be
addressed optically.},
Doi = {10.1021/nn901002q},
Key = {fds234807}
}
@article{fds234808,
Author = {Siegel, AC and Phillips, ST and Wiley, BJ and Whitesides,
GM},
Title = {Thin, lightweight, foldable thermochromic displays on
paper.},
Journal = {Lab on a chip},
Volume = {9},
Number = {19},
Pages = {2775-2781},
Year = {2009},
Month = {October},
ISSN = {1473-0197},
url = {http://dx.doi.org/10.1039/b905832j},
Abstract = {This article describes an electronic display that is
fabricated by patterning electrically conductive wires
(heaters) with micron-scale dimensions on one side of a
sheet of paper, and thermochromic ink on the opposite side.
Passing electrical current through the wires heats the paper
and changes the thermochromic ink from colored (black,
green, or other colors) to transparent; this change in
property reveals the paper underneath the ink-exposing any
messages printed on the paper-and serves as the basis for a
two-state "shutter" display. This type of display is thin
(100 microm), flat, lightweight (the display weighs <20
mg/cm(2)), can be folded, rolled, twisted, and creased while
maintaining function, and ultimately can (if required) be
disposed of by incineration. The display is appropriate for
applications where information must be presented clearly
(usually only once) for little cost (each display costs
<$0.10/m(2) in materials) and where limited electrical power
is available.},
Doi = {10.1039/b905832j},
Key = {fds234808}
}
@article{fds234810,
Author = {Jones, AC and Olmon, RL and Skrabalak, SE and Wiley, BJ and Xia, YN and Raschke, MB},
Title = {Mid-IR plasmonics: near-field imaging of coherent plasmon
modes of silver nanowires.},
Journal = {Nano letters},
Volume = {9},
Number = {7},
Pages = {2553-2558},
Year = {2009},
Month = {July},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl900638p},
Abstract = {Chemically synthesized metallic nanostructures can exhibit a
strong local optical field enhancement associated with their
high degree of crystallinity and well-defined
geometry-dependent surface plasmon resonances. The extension
of the plasmon modes into the mid-IR spectral range (3-30
microm) is shown for micrometer-sized nanowires with high
aspect ratios available in the form of pentagonally twinned
Ag crystallites as grown by polyol synthesis. Using
scattering-scanning near-field optical microscopy, the
associated IR plasmon modes are identified, and their
underlying spatial distribution and enhancement of the
optical polarization density is measured via phase,
amplitude, and polarization resolved optical vector-field
mapping. The transition from dipolar to multipolar
resonances is observed and described by modeling the Ag
wires using a modified cylindrical waveguide theory. For
10.6 microm excitation, dipole antenna resonances are
observed at a resonant length of L = lambda(eff)/2 with
lambda(eff) approximately 10.6 microm/(1.8 +/- 0.5)
approximately 6 +/- 2 microm. This effective wavelength
scaling is the result of electronic damping, despite the
high aspect ratios of the wires of order 1:10 to 1:200. With
the optical cycle period tau(IR) being comparable to the
Drude relaxation time of tau approximately 40 fs the mid-IR
defines the low-energy limit of the coherent plasmon regime
(tau(IR) less, similar tau) at the transition to purely
geometric antenna resonances (tau(IR) > tau).},
Doi = {10.1021/nl900638p},
Key = {fds234810}
}
@article{fds234812,
Author = {Thomas, SW and Chiechi, RC and LaFratta, CN and Webb, MR and Lee, A and Wiley, BJ and Zakin, MR and Walt, DR and Whitesides,
GM},
Title = {Infochemistry and infofuses for the chemical storage and
transmission of coded information.},
Journal = {Proceedings of the National Academy of Sciences of the
United States of America},
Volume = {106},
Number = {23},
Pages = {9147-9150},
Year = {2009},
Month = {June},
ISSN = {0027-8424},
url = {http://dx.doi.org/10.1073/pnas.0902476106},
Abstract = {This article describes a self-powered system that uses
chemical reactions--the thermal excitation of alkali
metals--to transmit coded alphanumeric information. The
transmitter (an "infofuse") is a strip of the flammable
polymer nitrocellulose patterned with alkali metal ions;
this pattern encodes the information. The wavelengths of 2
consecutive pulses of light represent each alphanumeric
character. While burning, infofuses transmit a sequence of
pulses (at 5-20 Hz) of atomic emission that correspond to
the sequence of metallic salts (and therefore to the encoded
information). This system combines information technology
and chemical reactions into a new area--"infochemistry"--that
is the first step toward systems that combine sensing and
transduction of chemical signals with multicolor
transmission of alphanumeric information.},
Doi = {10.1073/pnas.0902476106},
Key = {fds234812}
}
@article{fds234846,
Author = {Wiley, BJ and Lipomi, DJ and Bao, J and Capasso, F and Whitesides,
GM},
Title = {Fabrication of surface plasmon resonators by nanoskiving
single-crystalline gold microplates},
Journal = {Proceedings of SPIE - The International Society for Optical
Engineering},
Volume = {7205},
Number = {9},
Pages = {3023-3028},
Publisher = {SPIE},
Year = {2009},
Month = {May},
ISSN = {0277-786X},
url = {http://dx.doi.org/10.1117/12.807813},
Abstract = {This paper demonstrates the sectioning of chemically
synthesized, single-crystalline microplates of gold with an
ultramicrotome to produce single-crystalline nanowires. This
method produces collinearly aligned nanostructures with
small, regular changes in dimension with each consecutive
cross-section. The diamond knife cuts cleanly through
microplates 100 nm thick without bending the resulting
nanowire, and cuts through the sharp edges of a crystal to
generate nanoscale tips. This paper demonstrates that the
smooth surface of the single-crystalline gold nanowires
allows them to guide plasmons with lower loss than rough,
polycrystalline nanowires, and that the sharp tips on the
singlecrystalline nanowires serve as optical antenna that
selectively couple light into the nanowire at the resonance
frequency of the sharp tip. © 2009 SPIE.},
Doi = {10.1117/12.807813},
Key = {fds234846}
}
@article{fds234809,
Author = {Stan, CA and Schneider, GF and Shevkoplyas, SS and Hashimoto, M and Ibanescu, M and Wiley, BJ and Whitesides, GM},
Title = {A microfluidic apparatus for the study of ice nucleation in
supercooled water drops},
Journal = {Lab on a Chip},
Volume = {9},
Number = {16},
Pages = {2293-2305},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2009},
Month = {January},
ISSN = {1473-0197},
url = {http://dx.doi.org/10.1039/b906198c},
Abstract = {This paper describes a microfluidic instrument that produces
drops of supercooled water suspended in a moving stream of
liquid fluorocarbon, and measures the temperatures at which
ice nucleates in the drops. A microfluidic chip containing a
monodisperse drop generator and a straight channel with 38
embedded resistance thermometers was placed in contact with
a seven-zone temperature-control plate and imaged under a
microscope with a high-speed camera. This instrument can
record the freezing temperatures of tens of thousands of
drops within minutes, with an accuracy of 0.4 °C. The
ice-nucleation temperatures in ∼80-m drops were reported
for the freezing of 37061 drops of pure water, and of 8898
drops of water seeded with silver iodide. Nucleation of ice
in pure water was homogenous and occurred at temperatures
between -36 and -37.8 °C, while water containing silver
iodide froze between -10 and -19 °C. The instrument
recorded the largest sets of individual freezing
temperatures (37061), had the fastest data acquisition rate
(75 measurements/s), and the best optical (3 m) and temporal
(70 s) resolutions among instruments designed to study
nucleation of ice. The dendritic growth of ice in 150-m
drops of supercooled water at -35 °C was observed and
imaged at a rate of 16000 frames/s. © 2009 The Royal
Society of Chemistry.},
Doi = {10.1039/b906198c},
Key = {fds234809}
}
@article{fds234811,
Author = {Moran, CH and Wainerdi, SM and Cherukuri, TK and Kittrell, C and Wiley,
BJ and Nicholas, NW and Curley, SA and Kanzius, JS and Cherukuri,
P},
Title = {Size-dependent joule heating of gold nanoparticles using
capacitively coupled radiofrequency fields},
Journal = {Nano Research},
Volume = {2},
Number = {5},
Pages = {400-405},
Publisher = {Springer Nature},
Year = {2009},
Month = {January},
ISSN = {1998-0124},
url = {http://dx.doi.org/10.1007/s12274-009-9048-1},
Abstract = {Capacitively coupled shortwave radiofrequency fields (13.56
MHz) resistively heat low concentrations (1 ppm) of gold
nanoparticles with a thermal power dissipation of 380 kW/g
of gold. Smaller diameter gold nanoparticles (< 50 nm) heat
at nearly twice the rate of larger diameter gold
nanoparticles (50 nm), which is attributed to the higher
resistivity of smaller gold nanostructures. A Joule heating
model has been developed to explain this phenomenon and
provides critical insights into the rational design and
engineering of nanoscale materials for noninvasive thermal
therapy of cancer. © 2009 Tsinghua University Press and
Springer-Verlag GmbH.},
Doi = {10.1007/s12274-009-9048-1},
Key = {fds234811}
}
@article{fds234848,
Author = {Lu, X and Rycenga, M and Skrabalak, SE and Wiley, B and Xia,
Y},
Title = {Chemical synthesis of novel plasmonic nanoparticles.},
Journal = {Annual review of physical chemistry},
Volume = {60},
Number = {60},
Pages = {167-192},
Year = {2009},
Month = {January},
ISSN = {0066-426X},
url = {http://dx.doi.org/10.1146/annurev.physchem.040808.090434},
Abstract = {Under the irradiation of light, the free electrons in a
plasmonic nanoparticle are driven by the alternating
electric field to collectively oscillate at a resonant
frequency in a phenomenon known as surface plasmon
resonance. Both calculations and measurements have shown
that the frequency and amplitude of the resonance are
sensitive to particle shape, which determines how the free
electrons are polarized and distributed on the surface. As a
result, controlling the shape of a plasmonic nanoparticle
represents the most powerful means of tailoring and
fine-tuning its optical resonance properties. In a
solution-phase synthesis, the shape displayed by a
nanoparticle is determined by the crystalline structure of
the initial seed produced and the interaction of different
seed facets with capping agents. Using polyol synthesis as a
typical example, we illustrate how oxidative etching and
kinetic control can be employed to manipulate the shapes and
optical responses of plasmonic nanoparticles made of either
Ag or Pd. We conclude by highlighting a few fundamental
studies and applications enabled by plasmonic nanoparticles
having well-defined and controllable shapes.},
Doi = {10.1146/annurev.physchem.040808.090434},
Key = {fds234848}
}
@article{fds234806,
Author = {Guo, X and Qiu, M and Bao, J and Wiley, BJ and Yang, Q and Zhang, X and Ma, Y and Yu, H and Tong, L},
Title = {Direct Coupling of Plasmonic and Photonic Nanowires for
Hybrid Nanophotonic Components and Circuits},
Journal = {Nano Lett.},
Volume = {9},
Number = {12},
Pages = {4515-4519},
Year = {2009},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl902860d},
Abstract = {We report direct coupling of plasmonic and photonic
nanowires using ultracompact near-field interaction.
Photon-plasmon coupling efficiency up to 80% with coupling
length down to the 200 nm level is achieved between
individual Ag and ZnO nanowires. Hybrid nanophotonic
components, including polarization splitters, Mach-Zehnder
interferometers, and microring cavities, are fabricated out
of coupled Ag and ZnO nanowires. These components offer
relatively low loss with subwavelength confinement; a hybrid
nanowire microcavity exhibits a Q-factor of
520.},
Doi = {10.1021/nl902860d},
Key = {fds234806}
}
@article{fds234847,
Author = {Martinez, AW and Phillips, ST and Wiley, BJ and Gupta, M and Whitesides,
GM},
Title = {FLASH: a rapid method for prototyping paper-based
microfluidic devices.},
Journal = {Lab on a chip},
Volume = {8},
Number = {12},
Pages = {2146-2150},
Year = {2008},
Month = {December},
ISSN = {1473-0197},
url = {http://dx.doi.org/10.1039/b811135a},
Abstract = {This article describes FLASH (Fast Lithographic Activation
of Sheets), a rapid method for laboratory prototyping of
microfluidic devices in paper. Paper-based microfluidic
devices are emerging as a new technology for applications in
diagnostics for the developing world, where low cost and
simplicity are essential. FLASH is based on
photolithography, but requires only a UV lamp and a
hotplate; no clean-room or special facilities are required
(FLASH patterning can even be performed in sunlight if a UV
lamp and hotplate are unavailable). The method provides
channels in paper with dimensions as small as 200 microm in
width and 70 microm in height; the height is defined by the
thickness of the paper. Photomasks for patterning
paper-based microfluidic devices can be printed using an
ink-jet printer or photocopier, or drawn by hand using a
waterproof black pen. FLASH provides a straightforward
method for prototyping paper-based microfluidic devices in
regions where the technological support for conventional
photolithography is not available.},
Doi = {10.1039/b811135a},
Key = {fds234847}
}
@article{fds234789,
Author = {Pyayt, AL and Wiley, B and Xia, Y and Chen, A and Dalton,
L},
Title = {Integration of photonic and silver nanowire plasmonic
waveguides.},
Journal = {Nature nanotechnology},
Volume = {3},
Number = {11},
Pages = {660-665},
Year = {2008},
Month = {November},
ISSN = {1748-3387},
url = {http://dx.doi.org/10.1038/nnano.2008.281},
Abstract = {Future optical data transmission modules will require the
integration of more than 10,000 x 10,000 input and output
channels to increase data transmission rates and capacity.
This level of integration, which greatly exceeds that of a
conventional diffraction-limited photonic integrated
circuit, will require the use of waveguides with a mode
confinement below the diffraction limit, and also the
integration of these waveguides with diffraction-limited
components. We propose to integrate multiple silver nanowire
plasmonic waveguides with polymer optical waveguides for the
nanoscale confinement and guiding of light on a chip. In our
device, the nanowires lay perpendicular to the polymer
waveguide with one end inside the polymer. We theoretically
predict and experimentally demonstrate coupling of light
into multiple nanowires from the same waveguide, and also
demonstrate control over the degree of coupling by changing
the light polarization.},
Doi = {10.1038/nnano.2008.281},
Key = {fds234789}
}
@article{fds234844,
Author = {Rang, M and Jones, AC and Zhou, F and Li, Z-Y and Wiley, BJ and Xia, Y and Raschke, MB},
Title = {Optical near-field mapping of plasmonic nanoprisms.},
Journal = {Nano letters},
Volume = {8},
Number = {10},
Pages = {3357-3363},
Year = {2008},
Month = {October},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl801808b},
Abstract = {The optical local-field enhancement on nanometer length
scales provides the basis for plasmonic metal nanostructures
to serve as molecular sensors and as nanophotonic devices.
However, particle morphology and the associated surface
plasmon resonance alone do not uniquely reflect the
important details of the local field distribution. Here, we
use interferometric homodyne tip-scattering near-field
microscopy for plasmonic near-field imaging of crystalline
triangular silver nanoprisms. Strong spatial field variation
on lengths scales as short as 20 nm are observed sensitively
depending on structural details and environment. The poles
of the dipole and quadrupole plasmon modes, as identified by
phase-sensitive probing and calculations performed in the
discrete dipole approximation (DDA), reflect the particle
symmetry. Together with the observation that the largest
enhancement is not necessarily found to be associated with
the tips of the nanoprisms, our results provide critical
information for the selection of particle geometries as
building blocks for plasmonic device applications.},
Doi = {10.1021/nl801808b},
Key = {fds234844}
}
@article{fds318089,
Author = {Wiley, BJ and Lipomi, DJ and Bao, J and Capasso, F and Whitesides,
GM},
Title = {Fabrication of surface plasmon resonators by nanoskiving
single-crystalline gold microplates.},
Journal = {Nano letters},
Volume = {8},
Number = {9},
Pages = {3023-3028},
Year = {2008},
Month = {September},
url = {http://dx.doi.org/10.1021/nl802252r},
Abstract = {This paper demonstrates the sectioning of chemically
synthesized, single-crystalline microplates of gold with an
ultramicrotome (nanoskiving) to produce single-crystalline
nanowires; these nanowires act as low-loss surface plasmon
resonators. This method produces collinearly aligned
nanostructures with small, regular changes in dimension with
each consecutive cross-section: a single microplate thus can
produce a number of "quasi-copies" (delicately modulated
variations) of a nanowire. The diamond knife cuts cleanly
through microplates 35 microm in diameter and 100 nm thick
without bending the resulting nanowire and cuts through the
sharp edges of a crystal without deformation to generate
nanoscale tips. This paper compares the influence of sharp
tips and blunt tips on the resonator modes in these
nanowires.},
Doi = {10.1021/nl802252r},
Key = {fds318089}
}
@article{fds234843,
Author = {Skrabalak, SE and Wiley, BJ and Kim, M and Formo, EV and Xia,
Y},
Title = {On the polyol synthesis of silver nanostructures:
glycolaldehyde as a reducing agent.},
Journal = {Nano letters},
Volume = {8},
Number = {7},
Pages = {2077-2081},
Year = {2008},
Month = {July},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl800910d},
Abstract = {The polyol synthesis is a popular method of preparing metal
nanostructures, yet the mechanism by which metal ions are
reduced is poorly understood. Using a spectrophotometric
method, we show, for the first time, that heating ethylene
glycol (EG) in air results in its oxidation to
glycolaldehyde (GA), a reductant capable of reducing most
noble metal ions. The dependence of reducing power on
temperature for EG can be explained by this
temperature-dependent oxidation, and the factors influencing
GA production can have a profound impact on the nucleation
and growth kinetics. These new findings provide critical
insight into how the polyol synthesis can be used to
generate metal nanostructures with well-controlled shapes.
For example, with the primary reductant identified, it
becomes possible to evaluate and understand its explicit
role in generating nanostructures of a specific shape to the
exclusion of others.},
Doi = {10.1021/nl800910d},
Key = {fds234843}
}
@article{fds234842,
Author = {Kim, MH and Lu, X and Wiley, B and Lee, EP and Xia, Y},
Title = {Morphological evolution of single-crystal Ag nanospheres
during the galvanic replacement reaction with
HAuCl4},
Journal = {Journal of Physical Chemistry C},
Volume = {112},
Number = {21},
Pages = {7872-7876},
Publisher = {American Chemical Society (ACS)},
Year = {2008},
Month = {May},
ISSN = {1932-7447},
url = {http://dx.doi.org/10.1021/jp711662f},
Abstract = {This paper presents a systematic study of the galvanic
replacement reaction between 23.5 nm single-crystal Ag
nanospheres and HAuCl4 in an aqueous medium. We have
monitored both morphological and spectral changes as the
molar ratio of HAuCl4 to Ag is increased. The replacement
reaction on single-crystal Ag nanospheres results in the
formation of a series of hollow and porous nanostnictures
composed of Au-Ag alloys. By varying the molar ratio of
HAuCl4 to Ag, we are able to control the size and density of
the pores. In addition, the localized surface plasmon
resonance peaks of these nanostructures can be readily tuned
from 408 to 791 nm as the product becomes increasingly more
hollow and porous. © 2008 American Chemical
Society.},
Doi = {10.1021/jp711662f},
Key = {fds234842}
}
@article{fds234845,
Author = {Pyayt, AL and Wiley, BJ and Xia, Y and Chen, A and Dalton,
L},
Title = {Integration of Silver Nanowire Plasmonic and Photonic
Waveguides},
Journal = {Nature Photonics},
Number = {3},
Pages = {660-665},
Year = {2008},
Key = {fds234845}
}
@article{fds234841,
Author = {Xiong, Y and Wiley, BJ and Xia, Y},
Title = {Nanocrystals with unconventional shapes - A class of
promising catalysts},
Journal = {Angewandte Chemie - International Edition},
Volume = {46},
Number = {38},
Pages = {7157-7159},
Publisher = {WILEY},
Year = {2007},
Month = {October},
ISSN = {1433-7851},
url = {http://dx.doi.org/10.1002/anie.200702473},
Abstract = {Size and shape do matter sometimes: Nanocrystals of noble
metals are attractive for use as catalysts because of their
high surface-to-volume ratios and high surface energies,
which result in their surface atoms being highly active.
Recently reported platinum nanocrystals with a novel
tetrahexahedral shape reveal an enhanced catalytic activity
over their "amorphous" nanoparticle counterparts. (Figure
Presented). © 2007 Wiley-VCH Verlag GmbH & Co.
KGaA.},
Doi = {10.1002/anie.200702473},
Key = {fds234841}
}
@article{fds234840,
Author = {Wiley, B and Sun, Y and Xia, Y},
Title = {Synthesis of silver nanostructures with controlled shapes
and properties},
Journal = {Accounts of Chemical Research},
Volume = {40},
Number = {10},
Pages = {1067-1076},
Publisher = {American Chemical Society (ACS)},
Year = {2007},
Month = {October},
ISSN = {0001-4842},
url = {http://dx.doi.org/10.1021/ar7000974},
Abstract = {Mastery over the shape of a nanostructure enables control
over its properties and usefulness for a given application.
By controlling the crystallinity of the seeds from which
nanostructures grow and the rate of atomic addition to
seeds, we selectively produced pentagonal nanowires,
cuboctahedra, nanocubes, nanobars, bipyramids, and nanobeams
of silver with a solution-phase polyol synthesis. The
example of nanobars illustrates how the shape of a silver
nanostructure affects the color of light that it scatters.
We further show how silver nanowires and nanobeams can serve
as conduits for both electrons and photons. © 2007 American
Chemical Society.},
Doi = {10.1021/ar7000974},
Key = {fds234840}
}
@article{fds234835,
Author = {Fu, E and Ramsey, SA and Chen, J and Chinowsky, TM and Wiley, B and Xia, Y and Yager, P},
Title = {Resonance wavelength-dependent signal of absorptive
particles in surface plasmon resonance-based
detection},
Journal = {Sensors and Actuators, B: Chemical},
Volume = {123},
Number = {1},
Pages = {606-613},
Publisher = {Elsevier BV},
Year = {2007},
Month = {April},
ISSN = {0925-4005},
url = {http://dx.doi.org/10.1016/j.snb.2006.09.059},
Abstract = {We describe the resonance wavelength-dependent signal of
absorptive particles in surface plasmon resonance
(SPR)-based detection using both modeling and experimental
results. The particles, gold nanocages, have a significant
absorption cross-section in the near-infrared (NIR),
resulting in a wavelength-dependent refractive index as
measured by SPR. The SPR signal due to the nanocages varies
by four-fold over resonance wavelengths from 650 nm to 950
nm. The greatest SPR signal occurs at the longest resonance
wavelengths; its magnitude is due to the inherent increase
in sensitivity of SPR on gold with increasing wavelength and
the optical absorption properties of the nanocages. © 2006
Elsevier B.V. All rights reserved.},
Doi = {10.1016/j.snb.2006.09.059},
Key = {fds234835}
}
@article{fds234839,
Author = {Chen, J and Wiley, BJ and Xia, Y},
Title = {One-dimensional nanostructures of metals: Large-scale
synthesis and some potential applications},
Journal = {Langmuir},
Volume = {23},
Number = {8},
Pages = {4120-4129},
Publisher = {American Chemical Society (ACS)},
Year = {2007},
Month = {April},
ISSN = {0743-7463},
url = {http://dx.doi.org/10.1021/la063193y},
Abstract = {We review recent developments in our group regarding the
solution-phase synthesis of one-dimensional nanostructures
of metals. The synthetic approaches include
solution-liquid-solid growth for nanowires of
low-melting-point metals such as Pb; seed-directed growth
for Ag nanowires, nanobeams, and nanobelts; kinetically
controlled growth for Pt nanorods, nanowires, and multipods;
and galvanic replacement for nanotubes of Au, Pt, and Pd.
Both characterization and mechanistic studies are presented
for each nanostructure. Finally, we highlight the electrical
and plasmonic properties of these metal nanostructures and
discuss their potential applications in nanoscale devices.
© 2007 American Chemical Society.},
Doi = {10.1021/la063193y},
Key = {fds234839}
}
@article{fds234837,
Author = {Wiley, BJ and Chen, Y and McLellan, JM and Xiong, Y and Li, Z-Y and Ginger,
D and Xia, Y},
Title = {Synthesis and optical properties of silver nanobars and
nanorice.},
Journal = {Nano letters},
Volume = {7},
Number = {4},
Pages = {1032-1036},
Year = {2007},
Month = {April},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl070214f},
Abstract = {Silver nanobars with rectangular side facets and an average
aspect ratio of 2.7 have been synthesized by modifying the
concentration of bromide added to a polyol synthesis.
Subsequent rounding of nanobars transformed them into
nanorice. Due to their anisotropy, nanobars and nanorice
exhibit two plasmon resonance peaks, scattering light both
in the visible and in the near-infrared regions. With a
combination of discrete-dipole approximation calculations
and single-nanoparticle spectroscopy, we explored the effect
of nanostructure aspect ratio and corner sharpness on the
frequency of plasmon resonance. Near-field calculations and
surface-enhanced Raman scattering measurements on single
particles were performed to show how local field enhancement
changes with both the wavelength and polarization of
incident light.},
Doi = {10.1021/nl070214f},
Key = {fds234837}
}
@article{fds234838,
Author = {Xiong, Y and Cai, H and Wiley, BJ and Wang, J and Kim, MJ and Xia,
Y},
Title = {Synthesis and mechanistic study of palladium nanobars and
nanorods},
Journal = {Journal of the American Chemical Society},
Volume = {129},
Number = {12},
Pages = {3665-3675},
Publisher = {American Chemical Society (ACS)},
Year = {2007},
Month = {March},
ISSN = {0002-7863},
url = {http://dx.doi.org/10.1021/ja0688023},
Abstract = {This paper describes a simple and versatile method for
growing highly anisotropic nanostructures of Pd,
single-crystal nanobars bounded by {100} facets and
single-crystal nanorods with their side surfaces enclosed by
{100} and {110} facets. According to thermodynamic
arguments, Pd atoms should nucleate and grow in a solution
phase to form cuboctahedrons of spherical shape with their
surfaces bounded by a mix of {111} and {100} facets.
Anisotropic nanostructures can only form under kinetically
controlled conditions, while the cubic symmetry is broken.
In the present system, we found that one-dimensional growth
could be induced and maintained through an interplay of the
following processes: (i) speedy reduction of the precursor
to ensure prompt addition of atoms to the seed; (ii)
chemisorption of bromide on the seed to promote the
formation of {100} and {110} facets; and (iii) localized
oxidative etching on one specific face of the seed to
initiate preferential growth on this face. Experimentally,
the anisotropic growth can be achieved by varying the type
and concentration of reducing agent, as well as by adjusting
the reaction temperature. This methodology developed for Pd
has also been extended to both Au and Pt. As expected for a
kinetically controlled product, the anisotropic
nanostructure evolved into the thermodynamically favored
shape during an aging process. © 2007 American Chemical
Society.},
Doi = {10.1021/ja0688023},
Key = {fds234838}
}
@article{fds234836,
Author = {Petrova, H and Lin, CH and De Liejer and S and Hu, M and McLellan, JM and Siekkinen, AR and Wiley, BJ and Marquez, M and Xia, Y and Sader, JE and Hartland, GV},
Title = {Time-resolved spectroscopy of silver nanocubes: Observation
and assignment of coherently excited vibrational
modes},
Journal = {Journal of Chemical Physics},
Volume = {126},
Number = {9},
Pages = {094709},
Year = {2007},
Month = {March},
ISSN = {0021-9606},
url = {http://dx.doi.org/10.1063/1.2672907},
Abstract = {The response of single crystal, cubic silver particles to
ultrafast laser-induced heating has been examined
experimentally and theoretically. The transient absorption
traces display clear modulations due to coherently excited
vibrational modes. Nanocube samples with edge lengths
smaller than 50 nm show a single modulation, whereas samples
larger than 50 nm show two vibrational modes. The results
are compared to finite element calculations, where the cubes
are modeled as having cubic crystal symmetry with the
principal axes parallel to the sides of the particle. The
action of the laser pulse is treated in two ways, first, as
creating a uniform initial strain. In this case the
predominant mode excited is the breathing mode. The period
of this mode is in reasonable agreement with the vibrational
periods measured for the smaller cubes and with the higher
frequency modulation observed for the larger cubes. A
nonuniform initial strain is also considered, which could
arise from nonuniform heating for particles larger than the
optical skin depth of the metal. In this case the
predominant mode excited is a nontotally symmetric mode. The
calculated periods from this analysis are in reasonable
agreement with the lower frequency modulations observed for
the larger samples. The results from this study show that,
to within the accuracy of these measurements, the elastic
constants of cubic silver nanoparticles are the same as bulk
silver. © 2007 American Institute of Physics.},
Doi = {10.1063/1.2672907},
Key = {fds234836}
}
@article{fds234787,
Author = {Petrova, H and Lin, CH and De Leijer and S and Hu, M and McLellan, JM and Siekkinen, AR and Wiley, BJ and Marquez, M and Xia, Y and Sader, JE and Hartland, GV},
Title = {Vibrational spectroscopy and energy relaxation of nanocubes,
nanoboxes and nanocages},
Journal = {Proceedings of SPIE - The International Society for Optical
Engineering},
Volume = {6325},
Publisher = {SPIE},
Year = {2006},
Month = {November},
ISSN = {0277-786X},
url = {http://dx.doi.org/10.1117/12.678406},
Abstract = {Irradiating metal particles by an ultrafast laser pulse
produces rapid heating of the lattice. This can lead to
coherent excitation of the vibrational modes of the particle
that correlate with the expansion co-ordinates. By comparing
the measured periods to continuum mechanics calculations,
these experiments can provide information about the elastic
constants of the particle if the size and shape are known.
In this paper recent results are presented for particles
with cubic symmetry, specifically, nanocubes, nanoboxes
(hollow cubes) and nanocages (nanoboxes with holes on the
corners and/or facets of the box). The way the vibrational
modes are assigned, and the information content of the
experiments will be discussed, as well as the energy
relaxation dynamics of the particles. Energy relaxation is
important for the proposed use of the nanocages in
phothermal therapy, where heat dissipation following laser
excitation is used to selectively kill cells.},
Doi = {10.1117/12.678406},
Key = {fds234787}
}
@article{fds234833,
Author = {Wiley, BJ and Wang, Z and Wei, J and Yin, Y and Cobden, DH and Xia,
Y},
Title = {Synthesis and electrical characterization of silver
nanobeams.},
Journal = {Nano letters},
Volume = {6},
Number = {10},
Pages = {2273-2278},
Year = {2006},
Month = {October},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl061705n},
Abstract = {By slowing the rate of atomic addition to singly twinned
seeds, we have grown silver nanobeams with lengths of 3-30
mum, widths ranging from 17 to 70 nm, and a width to
thickness ratio of 1.4. The well-defined dimensions, smooth
surface, and crystallinity of nanobeams make them promising
candidates for studying the effects of size on electron
transport. With a simple method that allows rapid
characterization of single nanobeams, we find that even the
thinnest nanobeams largely retain the low resistivity of
bulk silver. Nanobeams can support remarkably high current
densities of up to 2.6 x 10(8) A cm(-2) before the
conduction path is broken by the formation of a
nanogap.},
Doi = {10.1021/nl061705n},
Key = {fds234833}
}
@article{fds234834,
Author = {Meng, L and Wei, H and Nagel, A and Wiley, BJ and Scriven, LE and Norris,
DJ},
Title = {The role of thickness transitions in convective
assembly.},
Journal = {Nano letters},
Volume = {6},
Number = {10},
Pages = {2249-2253},
Year = {2006},
Month = {October},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl061626b},
Abstract = {Here we examine the microscopic details of convective
assembly, a process in which thin colloidal crystals are
deposited on a substrate from suspensions of nearly
monodisperse spheres. Previously, such crystals have been
shown to exhibit a strong tendency toward the face-centered
cubic structure, which is difficult to explain on
thermodynamic grounds. Using real-time microscopic
visualization, electron microscopy, and scanning confocal
microscopy, we obtain clues about the crystallization
mechanism. Our results indicate that the regions at which a
growing crystal transitions from n to n + 1 layers can play
an important and previously unrecognized role in the
crystallization. For thin crystals, we show both from
experiment and through simple modeling that these transition
regions can generate specific crystal structures. In thicker
crystals, the crystallization is more complicated, but the
transition regions must still be considered before a
complete understanding of convective assembly can be
obtained.},
Doi = {10.1021/nl061626b},
Key = {fds234834}
}
@article{fds234831,
Author = {Wiley, BJ and Im, SH and Li, ZY and McLellan, J and Siekkinen, A and Xia,
Y},
Title = {Maneuvering the surface plasmon resonance of silver
nanostructures through shape-controlled synthesis},
Journal = {Journal of Physical Chemistry B},
Volume = {110},
Number = {32},
Pages = {15666-15675},
Publisher = {American Chemical Society (ACS)},
Year = {2006},
Month = {August},
ISSN = {1520-6106},
url = {http://dx.doi.org/10.1021/jp0608628},
Abstract = {Silver nanostructures are containers for surface plasmons -
the collective oscillation of conduction electrons in phase
with incident light. By controlling the shape of the
container, one can control the ways in which electrons
oscillate, and in turn how the nanostructure scatters light,
absorbs light, and enhances local electric fields. With a
series of discrete dipole approximation (DDA) calculations,
each of a distinctive morphology, we illustrate how shape
control can tune the optical properties of silver
nanostructures. Calculated predictions are validated by
experimental measurements performed on nanocubes with
controllable corner truncation, right bipyramids, and
pentagonal nanowires. Control of nanostructure shape allows
optimization of plasmon resonance for molecular detection
and spectroscopy. © 2006 American Chemical
Society.},
Doi = {10.1021/jp0608628},
Key = {fds234831}
}
@article{fds234832,
Author = {Sanders, AW and Routenberg, DA and Wiley, BJ and Xia, Y and Dufresne,
ER and Reed, MA},
Title = {Observation of plasmon propagation, redirection, and fan-out
in silver nanowires.},
Journal = {Nano letters},
Volume = {6},
Number = {8},
Pages = {1822-1826},
Year = {2006},
Month = {August},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl052471v},
Abstract = {We report the coupling of free-space photons (vacuum
wavelength of 830 nm) to surface plasmon modes of a silver
nanowire. The launch of propagating plasmons, and the
subsequent emission of photons, is selective and occurs only
at ends and other discontinuities of the nanowire. In
addition, we observe that the nanowires redirect the
plasmons through turns of radii as small as 4 microm. We
exploit the radiating nature of discontinuities to find a
plasmon propagation length >3 +/- 1 microm. Finally, we
observe that interwire plasmon coupling occurs for
overlapping wires, demonstrating plasmon fan-out at
subwavelength scales.},
Doi = {10.1021/nl052471v},
Key = {fds234832}
}
@article{fds234830,
Author = {Wiley, BJ and Xiong, Y and Li, Z-Y and Yin, Y and Xia,
Y},
Title = {Right bipyramids of silver: a new shape derived from single
twinned seeds.},
Journal = {Nano letters},
Volume = {6},
Number = {4},
Pages = {765-768},
Year = {2006},
Month = {April},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl060069q},
Abstract = {Silver nanoparticles with a single (111) twin were
selectively nucleated and grown for the first time to
produce right bipyramids 75-150 nm in edge length. Key to
the production of single twinned seeds was the addition of
NaBr to a polyol synthesis in which AgNO3 is reduced by
ethylene glycol in the presence of poly(vinyl pyrrolidone).
Examination of nanoparticles at different stages of the
reaction with electron microscopy revealed that the
spherical, single twinned seeds grew to become right
bipyramids through enlargement of their (100) facets. The
UV-vis-NIR spectrum exhibited by right bipyramids is
distinct from that of any other silver nanostructure, and
their sharp corners make these new nanoparticles especially
promising for enhancement of Raman scattering.},
Doi = {10.1021/nl060069q},
Key = {fds234830}
}
@article{fds234786,
Author = {Zettsu, N and McLellan, JM and Wiley, B and Yin, Y and Li, ZY and Xia,
Y},
Title = {Synthesis, stability, and surface plasmonic properties of
rhodium multipods, and their use as substrates for
surface-enhanced raman scattering},
Journal = {Angewandte Chemie - International Edition},
Volume = {45},
Number = {8},
Pages = {1288-1292},
Publisher = {WILEY},
Year = {2006},
Month = {February},
ISSN = {1433-7851},
url = {http://dx.doi.org/10.1002/anie.200503174},
Abstract = {(Graph Presented) Multipodal Rh nanocrystals (see HRTEM
image of a tripod) prepared through a polyol synthesis
display surface plasmon resonance bands in the visible
region. Surface-enhanced Raman scattering from
4-mercaptopyridine adsorbed on Rh multipods is 19-times
stronger than that from Rh nanocubes. © 2006 Wiley-VCH
Verlag GmbH & Co. KGaA.},
Doi = {10.1002/anie.200503174},
Key = {fds234786}
}
@article{fds234771,
Author = {Chen, J and Saeki, F and Wiley, BJ and Cang, H and Au, L and Zhang, H and Cobb, MJ and Kimmey, MB and Xia, Y and Li, X},
Title = {Bioconjugated Au/Ag nanocages as a novel optical imaging
contrast and thermal therapeutic agent},
Journal = {Optics InfoBase Conference Papers},
Year = {2006},
Month = {January},
ISSN = {2162-2701},
Abstract = {We have synthesized 40-nm Au/Ag nanocages and explored their
use as an optical imaging/spectroscopy contrast agent and
potentially a thermal therapeutic agent. Cancer cell
specific targeting by antibody-conjugated nanocages has also
been demonstrated. © 2005 Optical Society of
America.},
Key = {fds234771}
}
@article{fds234829,
Author = {Zettsu, N and McLellan, JM and Wiley, BJ and Yin, Y and Li, ZY and Xia,
Y},
Title = {Rhodium Multipods: Synthesis, Stability, Surface Plasmonic
Properties, and Their Use as Substrates for Surface-Enhanced
Raman Scattering},
Journal = {Angew. Chem. Int. Ed.},
Number = {45},
Pages = {1288-1292},
Year = {2006},
Key = {fds234829}
}
@article{fds234828,
Author = {Xiong, Y and Wiley, B and Chen, J and Li, ZY and Yin, Y and Xia,
Y},
Title = {Corrosion-based synthesis of single-crystal Pd nanoboxes and
nanocages and their surface plasmon properties},
Journal = {Angewandte Chemie - International Edition},
Volume = {44},
Number = {48},
Pages = {7913-7917},
Publisher = {WILEY},
Year = {2005},
Month = {December},
ISSN = {1433-7851},
url = {http://dx.doi.org/10.1002/anie.200502722},
Abstract = {(Figure Presented) Inside out: Corrosive pitting and etching
can be combined in a simple, elegant, and powerful method to
transform single-crystal Pd nanocubes into nanoboxes (see
SEM image) and nanocages in a one-pot synthesis without the
involvement of exotic templates. Emptying the interiors
enables the surface plasmon resonance peaks of the Pd
nanostructures to be tuned from 410 to 520 nm. © 2005
Wiley-VCH Verlag GmbH & Co. KGaA.},
Doi = {10.1002/anie.200502722},
Key = {fds234828}
}
@article{fds234770,
Author = {Chen, J and Saeki, F and Wiley, BJ and Gang, H and Au, L and Zhang, H and Cobb, MJ and Kimmey, MB and Xia, Y and Li, X},
Title = {Bioconjugated Au/Ag nanocages as a novel optical imaging
contrast and thermal therapeutic agent},
Journal = {2005 Conference on Lasers and Electro-Optics,
CLEO},
Volume = {3},
Pages = {2052-2054},
Year = {2005},
Month = {December},
ISSN = {2162-2701},
Abstract = {We have synthesized 40-nm Au/Ag nanocages and explored their
use as an optical imaging/spectroscopy contrast agent and
potentially a thermal therapeutic agent. Cancer cell
specific targeting by antibody-conjugated nanocages has also
been demonstrated. ©2005 Optical Society of
America.},
Key = {fds234770}
}
@article{fds234785,
Author = {Cang, H and Sun, T and Li, Z-Y and Chen, J and Wiley, BJ and Xia, Y and Li,
X},
Title = {Gold nanocages as contrast agents for spectroscopic optical
coherence tomography.},
Journal = {Optics letters},
Volume = {30},
Number = {22},
Pages = {3048-3050},
Year = {2005},
Month = {November},
ISSN = {0146-9592},
url = {http://dx.doi.org/10.1364/ol.30.003048},
Abstract = {We describe gold nanocages as a new class of potential
contrast agent for spectroscopic optical coherence
tomography (OCT). Monodispersed gold nanocages of an
approximately 35 nm edge length exhibit strong optical
resonance, with the peak wavelength tunable in the
near-infrared range. We characterized the optical properties
of the nanocage by using OCT experiments along with
numerical calculations, revealing an absorption cross
section approximately 5 orders of magnitude larger than
conventional dyes. Experiments with tissue phantoms
demonstrated that the nanocages provide enhanced contrast
for spectroscopic as well as conventional intensity-based
OCT imaging.},
Doi = {10.1364/ol.30.003048},
Key = {fds234785}
}
@article{fds234826,
Author = {Sherry, LJ and Chang, SH and Schatz, GC and Van Duyne and RP and Wiley, BJ and Xia, Y},
Title = {Localized surface plasmon resonance spectroscopy of single
silver nanocubes},
Journal = {Nano Letters},
Volume = {5},
Number = {10},
Pages = {2034-2038},
Publisher = {American Chemical Society (ACS)},
Year = {2005},
Month = {October},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl0515753},
Abstract = {In this work, we use dark-field microscopy to observe a new
plasmon resonance effect for a single silver nanocube in
which the plasmon line shape has two distinct peaks when the
particles are located on a glass substrate. The dependence
of the resonance on nanocube size and shape is
characterized, and it is found that the bluer peak has a
higher figure of merit for chemical sensing applications
than that for other particle shapes that have been studied
previously. Comparison of the measured results with finite
difference time domain (FDTD) electrodynamics calculations
enables us to confirm the accuracy of our spectral
assignments. © 2005 American Chemical Society.},
Doi = {10.1021/nl0515753},
Key = {fds234826}
}
@article{fds234827,
Author = {Chen, J and Wiley, B and McLellan, J and Xiong, Y and Li, ZY and Xia,
Y},
Title = {Optical properties of Pd-Ag and Pt-Ag nanoboxes synthesized
via galvanic replacement reactions},
Journal = {Nano Letters},
Volume = {5},
Number = {10},
Pages = {2058-2062},
Publisher = {American Chemical Society (ACS)},
Year = {2005},
Month = {October},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl051652u},
Abstract = {Silver nanocubes dispersed in water were transformed into
Pd-Ag or Pt-Ag nanoboxes by adding either Na 2PdCl 4 or Na
2PtCl 4. By controlling the amount of noble metal salt
added, and therefore the molar ratio of Na 2PdCl 4 or Na
2PtCl 4 to Ag, we could tune the surface plasmon resonance
peak of the nanostructures across the entire visible
spectrum, from 440 to 730 nm. Replacement of Ag with Pd
resulted in the formation of a nanobox composed of a Pd-Ag
alloy single crystal, but the nanobox formed after
replacement of Ag with Pt was instead composed of distinct
Pt nanoparticles. DDA calculations suggest that both
nanoboxes absorb light strongly, with Q abs/Q sca ≈ 5.
After galvanic replacement, Pd-Ag and Pt-Ag nanostructures
remain SERS active, suggesting their use as a SERS probe for
studying the dependence of interfacial chemistry on
composition. © 2005 American Chemical Society.},
Doi = {10.1021/nl051652u},
Key = {fds234827}
}
@article{fds234822,
Author = {Chen, J and Wiley, B and Li, ZY and Campbell, D and Saeki, F and Cang, H and Au, L and Lee, J and Li, X and Xia, Y},
Title = {Gold nanocages: Engineering their structure for biomedical
applications},
Journal = {Advanced Materials},
Volume = {17},
Number = {18},
Pages = {2255-2261},
Publisher = {WILEY},
Year = {2005},
Month = {September},
url = {http://dx.doi.org/10.1002/adma.200500833},
Abstract = {The galvanic replacement reaction between a Ag template and
HAuCl 4 in an aqueous solution transforms 30-200 nm Ag
nanocubes into Au nanoboxes and nanocages (nanoboxes with
porous walls). By controlling the molar ratio of Ag to
HAuCl4, the extinction peak of resultant structures can be
continuously tuned from the blue (400 nm) to the
near-infrared (1200 nm) region of the electromagnetic
spectrum. These hollow Au nanostructures are characterized
by extraordinarily large cross-sections for both absorption
and scattering. Optical coherence tomography measurements
indicate that the 36 nm nanocage has a scattering
cross-section of ∼ 0.8 × 10-15 m2 and an absorption
cross-section of ∼ 7.3 × 10 -15 m2. The absorption
cross-section is more than five orders of magnitude larger
than those of conventional organic dyes. Exposure of Au
nanocages to a camera flash resulted in the melting and
conversion of Au nanocages into spherical particles due to
photothermal heating. Discrete-dipole-approximation
calculations suggest that the magnitudes of both scattering
and absorption cross-sections of Au nanocages can be
tailored by controlling their dimensions, as well as the
thickness and porosity of their walls. This novel class of
hollow nanostructures is expected to find use as both a
contrast agent for optical imaging in early stage tumor
detection and as a therapeutic agent for photothermal cancer
treatment. © 2005 WILEY-VCH Verlag GmbH S. Co. KGaA,
Weinheim.},
Doi = {10.1002/adma.200500833},
Key = {fds234822}
}
@article{fds234825,
Author = {Wiley, B and Sun, Y and Xia, Y},
Title = {Polyol synthesis of silver nanostructures: Control of
product morphology with Fe(II) or Fe(III)
Species},
Journal = {Langmuir},
Volume = {21},
Number = {18},
Pages = {8077-8080},
Publisher = {American Chemical Society (ACS)},
Year = {2005},
Month = {August},
ISSN = {0743-7463},
url = {http://dx.doi.org/10.1021/la050887i},
Abstract = {Adjusting the concentration of Fe(II) or Fe(III) in the
polyol reduction of silver nitrate allows for the production
of either nanocubes or nanowires. Reduction by ethylene
glycol maintained the iron ions in the reduced Fe(II) form,
which in turn reacted with and removed adsorbed atomic
oxygen from the surface of silver nanoparticles. Relatively
high concentrations (2.2 μM) of iron ions facilitated the
growth of multiply twinned seeds to form nanowires by
removing oxygen from the surface of twinned seeds and
preventing their dissolution by oxidative etching. Lower
concentrations (<0.44μM) of iron ions only partially
removed oxygen from the surface, resulting in selective
etching of twinned seeds and accelerated formation of
single-crystal nanocubes. In each case, the addition of
chloride prevented rapid aggregation of seeds and
facilitated their growth into discrete nanostructures. ©
2005 American Chemical Society.},
Doi = {10.1021/la050887i},
Key = {fds234825}
}
@article{fds234823,
Author = {Lee, YT and Im, SH and Wiley, B and Xia, Y},
Title = {Quick formation of single-crystal nanocubes of silver
through dual functions of hydrogen gas in polyol
synthesis},
Journal = {Chemical Physics Letters},
Volume = {411},
Number = {4-6},
Pages = {479-483},
Publisher = {Elsevier BV},
Year = {2005},
Month = {August},
url = {http://dx.doi.org/10.1016/j.cplett.2005.06.080},
Abstract = {High yields of 40-nm silver nanocubes were produced in 20
min by bubbling hydrogen gas through a conventional polyol
synthesis. Hydrogen gas both accelerated the reduction rate
and generated nitric acid in situ. Twinned seeds were
selectively dissolved by balancing the reduction rate with
etching by nitric acid, so that only single crystals were
produced. © 2005 Elsevier B.V. All rights
reserved.},
Doi = {10.1016/j.cplett.2005.06.080},
Key = {fds234823}
}
@article{fds234821,
Author = {Xiong, Y and Chen, J and Wiley, B and Xia, Y and Yin, Y and Li,
Z-Y},
Title = {Size-dependence of surface plasmon resonance and oxidation
for Pd nanocubes synthesized via a seed etching
process.},
Journal = {Nano letters},
Volume = {5},
Number = {7},
Pages = {1237-1242},
Year = {2005},
Month = {July},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl0508826},
Abstract = {Pd nanocubes between 8 and 50 nm in size were synthesized at
the same concentration of Na2PdCl4 precursor by controlling
the number of seeds formed in the nucleation stage.
Increasing the concentration of FeCl3, an oxidative etchant
for Pd, reduced the number of seeds and led to formation of
larger Pd nanocubes. The larger nanocubes exhibited surface
plasmon resonance peaks in the visible region, the locations
of which matched with the results of the discrete dipole
approximation calculation. While the nanocubes of 25 and 50
nm in size oxidized in air to form Pd@PdO core-shell
structures, the 8-nm nanocubes were stable in air for over
90 days.},
Doi = {10.1021/nl0508826},
Key = {fds234821}
}
@article{fds234784,
Author = {Wang, Y and Lee, K and Shang, H and Wiley, B and Xia, Y and Cao,
G},
Title = {Ag-Ag 0.08v 2O 5·nH
2O composite films as host materials for Li
+ intercalation},
Journal = {Physica Status Solidi (A) Applications and Materials
Science},
Volume = {202},
Number = {8},
Pages = {R79-R81},
Publisher = {WILEY},
Year = {2005},
Month = {June},
ISSN = {1862-6300},
url = {http://dx.doi.org/10.1002/pssa.200510026},
Abstract = {We have prepared Ag-Ag 0.08V 2O 5· nH 2O composite films by
dispersing Ag nanowires into V 2O 5·nH 2O sol and have
investigated electrochemical properties of the films for Li
+-ion intercalation applications. With the molar ratio of Ag
nanowires to V 2O 5·nH 2O as 0.1, such prepared films are
composed of metallic Ag nanowires embedded in the matrix of
Ag 0.08V 2O 5·nH 2O, due to partial Ag reacted with V 2O
5·nH 2O. At a current density of 85 mA/g, such Ag-Ag 0.08V
2O 5·nH 2O film can intercalate about two equivalents of Li
ions and delivers twice the capacity of the V 2O 5·nH 2O
xerogel film. Such improved electrochemical performance is
ascribed to the changes in the microstructure and
crystallinity of the Ag-Ag 0.08V 2O 3·nH 2O films including
(i) further amorphization of V 2O 3·nH 2O, (ii) increased
porosity, and (iii) enhancement of electrical conductivity.
© 2005 WILEY-VCH Verlag GmbH & Co. KGaA,
Weinheim.},
Doi = {10.1002/pssa.200510026},
Key = {fds234784}
}
@article{fds234819,
Author = {Xiong, Y and Chen, J and Wiley, B and Xia, Y and Aloni, S and Yin,
Y},
Title = {Understanding the role of oxidative etching in the polyol
synthesis of Pd nanoparticles with uniform shape and
size.},
Journal = {Journal of the American Chemical Society},
Volume = {127},
Number = {20},
Pages = {7332-7333},
Year = {2005},
Month = {May},
ISSN = {0002-7863},
url = {http://dx.doi.org/10.1021/ja0513741},
Abstract = {Uniform cubooctahedral nanoparticles of Pd were synthesized
using a modified polyol process. Like the silver system, the
Pd nanoparticles underwent dissolution due to oxidative
etching by Cl-/O2. In the early stage of etching, the
twinned particles in a sample were selectively removed to
leave behind uniform, single-crystal cubooctahedra. If the
etching was allowed to continue, the single-crystal
cubooctahedra were also attacked and partially dissolved.
Understanding the role of oxidative etching is critical to
the achievement of both uniform shape and
size.},
Doi = {10.1021/ja0513741},
Key = {fds234819}
}
@article{fds234816,
Author = {Sang, HI and Yun, TL and Wiley, B and Xia, Y},
Title = {Large-scale synthesis of silver nanocubes: The role of HCl
in promoting cube perfection and monodispersity},
Journal = {Angewandte Chemie - International Edition},
Volume = {44},
Number = {14},
Pages = {2154-2157},
Publisher = {WILEY},
Year = {2005},
Month = {March},
url = {http://dx.doi.org/10.1002/anie.200462208},
Abstract = {(Chemical Equation Presented) One lump or two! Selective
etching of twinned seeds, mediated by HCl and the oxygen in
air, resulted in high yields of perfect single-crystal
silver nanocubes in a range of sizes (30-130 nm). The
chloride ion enhances oxidation and prevents aggregation,
while the proton decreases the rate of reduction and
facilitates etching through the formation of nitric acid. ©
2005 Wiley-VCH Verlag GmbH & Co. KGaA.},
Doi = {10.1002/anie.200462208},
Key = {fds234816}
}
@article{fds234817,
Author = {Chen, J and Saeki, F and Wiley, BJ and Cang, H and Cobb, MJ and Li, Z-Y and Au, L and Zhang, H and Kimmey, MB and Li, X and Xia,
Y},
Title = {Gold nanocages: bioconjugation and their potential use as
optical imaging contrast agents.},
Journal = {Nano letters},
Volume = {5},
Number = {3},
Pages = {473-477},
Year = {2005},
Month = {March},
ISSN = {1530-6984},
url = {http://dx.doi.org/10.1021/nl047950t},
Abstract = {Gold nanocages of <40 nm in dimension have been synthesized
using the galvanic replacement reaction between Ag nanocubes
and HAuCl4 in an aqueous solution. By controlling the molar
ratio between Ag and HAuCl4, the gold nanocages could be
tuned to display surface plasmon resonance peaks around 800
nm, a wavelength commonly used in optical coherence
tomography (OCT) imaging. OCT measurements on phantom
samples indicate that these gold nanocages have a moderate
scattering cross-section of approximately 8.10 x 10(-16) m2
but a very large absorption cross-section of approximately
7.26 x 10(-15) m2, suggesting their potential use as a new
class of contrast agents for optical imaging. When
bioconjugated with antibodies, the gold nanocages have also
been demonstrated for specific targeting of breast cancer
cells.},
Doi = {10.1021/nl047950t},
Key = {fds234817}
}
@article{fds234769,
Author = {Fu, E and Foley, J and Chen, J and Wiley, B and Xia, Y and Yager,
P},
Title = {Wavelength-dependent signal amplification potential of gold
nanocage tags for surface plasmon resonance (SPR)
imaging},
Journal = {Micro Total Analysis Systems - Proceedings of MicroTAS 2005
Conference: 9th International Conference on Miniaturized
Systems for Chemistry and Life Sciences},
Volume = {1},
Pages = {1510-1512},
Year = {2005},
Month = {January},
Abstract = {This paper reports an investigation of the surface plasmon
resonance (SPR) signal amplification potential of custom
synthesized 40 nm gold nanocages with localized surface
plasmon resonance (LSPR) in the near-infrared (NIR).
Copyright © 2005 by the Transducer Research Foundation,
Inc.},
Key = {fds234769}
}
@article{fds234781,
Author = {Chen, J and Saeki, F and Wiley, BJ and Cang, H and Au, L and Zhang, H and Cobb, MJ and Kimmey, MB and Xia, Y and Li, X},
Title = {Bioconjugated Au/Ag nanocages as a novel optical imaging
contrast and thermal therapeutic agent},
Journal = {Optics InfoBase Conference Papers},
Volume = {3},
Pages = {2052-2054},
Year = {2005},
Month = {January},
Abstract = {We have synthesized 40-nm Au/Ag nanocages and explored their
use as an optical imaging/spectroscopy contrast agent and
potentially a thermal therapeutic agent. Cancer cell
specific targeting by antibody-conjugated nanocages has also
been demonstrated. © 2005 Optical Society of
America.},
Key = {fds234781}
}
@article{fds234783,
Author = {Wiley, B and Sun, Y and Chen, J and Cang, H and Li, ZY and Li, X and Xia,
Y},
Title = {Shape-controlled synthesis of silver and gold
nanostructures},
Journal = {MRS Bulletin},
Volume = {30},
Number = {5},
Pages = {356-361},
Publisher = {Cambridge University Press (CUP)},
Year = {2005},
Month = {January},
ISSN = {0883-7694},
url = {http://dx.doi.org/10.1557/mrs2005.98},
Abstract = {This article provides a brief account of solution-phase
methods that generate silver and gold nanostructures with
well-controlled shapes. It is organized into five sections:
The first section discusses the nucleation and formation of
seeds from which nanostructures grow. The next two sections
explain how seeds with fairly isotropic shapes can grow
anisotropically into distinct morphologies. Polyol synthesis
is selected as an example to illustrate this concept.
Specifically, we discuss the growth of silver nanocubes
(with and without truncated corners), nanowires, and
triangular nanoplates. In the fourth section, we show that
silver nanostructures can be transformed into hollow gold
nanostructures through a galvanic replacement reaction.
Examples include nanoboxes, nanocages, nanotubes (both
single- and multi-walled), and nanorattles. The fifth
section briefly outlines a potential medical application for
gold nanocages. We conclude with some perspectives on areas
for future work.},
Doi = {10.1557/mrs2005.98},
Key = {fds234783}
}
@article{fds234815,
Author = {Wiley, B and Sun, Y and Mayers, B and Xia, Y},
Title = {Shape-controlled synthesis of metal nanostructures: the case
of silver.},
Journal = {Chemistry (Weinheim an der Bergstrasse, Germany)},
Volume = {11},
Number = {2},
Pages = {454-463},
Year = {2005},
Month = {January},
ISSN = {0947-6539},
url = {http://dx.doi.org/10.1002/chem.200400927},
Abstract = {The concept of shape-controlled synthesis is discussed by
investigating the growth mechanisms for silver nanocubes,
nanowires, and nanospheres produced through a
polymer-mediated polyol process. Experimental parameters,
such as the concentration of AgNO(3) (the precursor to
silver), the molar ratio between poly(vinylpyrrolidone)
(PVP, the capping agent) and AgNO(3), and the strength of
chemical interaction between PVP and various
crystallographic planes of silver, were found to determine
the crystallinity of seeds (e.g., single crystal versus
decahedral multiply twinned particles). In turn, the
crystallinity of a seed and the extent of the PVP coverage
on the seed were both instrumental in controlling the
morphology of final product. The ability to generate silver
nanostructures with well-defined morphologies provides a
great opportunity to experimentally and systematically study
the relationship between their properties and geometric
shapes.},
Doi = {10.1002/chem.200400927},
Key = {fds234815}
}
@article{fds234818,
Author = {Wiley, BJ and Sun, Y and Chen, J and Cang, H and Li, ZY and Li, X and Xia,
Y},
Title = {Silver and Gold Nanostructures with Well-Controlled
Shapes},
Journal = {MRS Bull.},
Number = {30},
Pages = {356-361},
Year = {2005},
Key = {fds234818}
}
@article{fds234820,
Author = {Wang, Y and Lee, K and Shang, H and Wiley, BJ and Xia, Y and Cao,
G},
Title = {Ag–Ag0.08V2O5·nH2O Composite Films as Host Materials for
Li-ion Intercalation},
Journal = {Phys. Stat. Sol. A},
Number = {202A},
Pages = {R79-R81},
Year = {2005},
Key = {fds234820}
}
@article{fds234824,
Author = {Cang, H and Sun, T and Chen, J and Wiley, BJ and Li, ZY and Xia, Y and Li,
X},
Title = {Gold Nanocages as Potential Contrast Agents for
Spectroscopic and Conventional Optical Coherence
Tomography},
Journal = {Opt. Lett.},
Number = {30},
Pages = {3048-3050},
Year = {2005},
Key = {fds234824}
}
@article{fds234782,
Author = {Wiley, B and Herricks, T and Sun, Y and Xia, Y},
Title = {Erratum: Polyol synthesis of silver nanoparticles. Use of
chloride and oxygen to promote the formation of
single-crystal, truncated cubes and tetrahedrons (NANO
Letters (2004) 4 (1734))},
Journal = {Nano Letters},
Volume = {4},
Number = {10},
Pages = {2057},
Publisher = {American Chemical Society (ACS)},
Year = {2004},
Month = {October},
url = {http://dx.doi.org/10.1021/nl048559a},
Doi = {10.1021/nl048559a},
Key = {fds234782}
}
@article{fds234814,
Author = {Wiley, B and Herricks, T and Sun, Y and Xia, Y},
Title = {Polyol synthesis of silver nanoparticles: Use of chloride
and oxygen to promote the formation of single-crystal,
truncated cubes and tetrahedrons},
Journal = {Nano Letters},
Volume = {4},
Number = {9},
Pages = {1733-1739},
Publisher = {American Chemical Society (ACS)},
Year = {2004},
Month = {September},
url = {http://dx.doi.org/10.1021/nl048912c},
Abstract = {Single-crystal cubes and tetrahedrons of silver with
truncated corners/edges have been prepared for the first
time in high yields by reducing silver nitrate with ethylene
glycol heated to 148°C in the presence of poly(vinyl
pyrrolidone) and a trace amount of sodium chloride. These
nanoparticles were relatively monodisperse in size and
shape, and their dimensions could be readily controlled in
the range of 20 to 80 nm by varying the reaction time and
other experimental parameters. We propose that the defects
inherent in twinned nuclei of silver led to their selective
etching and dissolution by chloride and oxygen (from air),
leaving only the single crystalline ones to grow into
nanoscale cubes and tetrahedrons.},
Doi = {10.1021/nl048912c},
Key = {fds234814}
}
@article{fds234813,
Author = {Sun, Y and Wiley, B and Li, ZY and Xia, Y},
Title = {Synthesis and optical properties of nanorattles and
multiple-walled nanoshells/nanotubes made of metal
alloys},
Journal = {Journal of the American Chemical Society},
Volume = {126},
Number = {30},
Pages = {9399-9406},
Publisher = {American Chemical Society (ACS)},
Year = {2004},
Month = {August},
url = {http://dx.doi.org/10.1021/ja048789r},
Abstract = {The galvanic replacement reaction between silver and
chloroauric acid has been exploited as a powerful means for
preparing metal nanostructures with hollow interiors. Here,
the utility of this approach is further extended to produce
complex core/shell nanostructures made of metals by
combining the replacement reaction with electroless
deposition of silver. We have fabricated nanorattles
consisting of Au/Ag alloy cores and Au/Ag alloy shells by
starting with Au/Ag alloy colloids as the initial template.
We have also prepared multiple-walled nanoshells/nanotubes
(or nanoscale Matrioshka) with a variety of shapes,
compositions, and structures by controlling the morphology
of the template and the precursor salt used in each step of
the replacement reaction. There are a number of interesting
optical features associated with these new core/shell metal
nanostructures. For example, nanorattles made of Au/Ag
alloys displayed two well-separated extinction peaks, a
feature similar to that of gold or silver nanorods. The peak
at ∼510 nm could be attributed to the Au/Ag alloy cores,
while the other peak was associated with the Au/Ag alloy
shells and could be continuously tuned in the spectral range
from red to near-infrared.},
Doi = {10.1021/ja048789r},
Key = {fds234813}
}
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