Preparation And Electrochemical Performance Of Nanostructured Mno2 Materials,
2012
Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of ChemistryInstitute of New Energy, Fudan University, Shanghai 200433, China
Preparation And Electrochemical Performance Of Nanostructured Mno2 Materials, Wen Wu, Dan-Dan Zhou, Meng-Yan Hou, Yong-Yao Xia
Journal of Electrochemistry
Nanostructured MnO2 materials were prepared in a micro-emulsion medium using sodium dodecyl sulfate (SDS）as a surfactant by a redox reaction between potassium permanganate and aniline. The morphologies of the obtained MnO2 were critically dependent on the concentrations of SDS. The particle sizes varied with the change in the micro-emulsion medium. The optimized properties of MnO2 material obtained with the surfactant concentration of 0.2 mol.L-1 had a specific surface area of 228.2 m2.g-1, and delivered a specific capacitance of 237 F.g -1 in 1 mol.L-1 Li2SO4. Additionally, a …
Carbon Nanotubes With Ni2P Nanoparticles As A Counter Electrode In Dye-Sensitized Solar Cells,
2012
Institute of New Energy Material Chemistry, Nankai University, Tianjin 300071, China
Carbon Nanotubes With Ni2P Nanoparticles As A Counter Electrode In Dye-Sensitized Solar Cells, Yan-Ye Dou, Nan-Fu Yan, Guo-Ran Li, Xue-Ping Gao
Journal of Electrochemistry
Carbon nanotubes (CNTs) supported by Ni2P nanoparticles are prepared and used as a counter electrode in dye-sensitized solar cells (DSSCs) for the first time. The CNTs-Ni2P composite was prepared by the heat treatment of a mixed precursor including nickel chloride, sodium hypophosphite and CNTs in argon atmosphere. The X-Ray diffraction (XRD) results indicate that the as-prepared sample consists of hexagonal Ni2P and carbon nanotubes. No peaks of other nickel phosphides are observed in the XRD pattern. Microstructure of the Ni2P-CNTs composite was investigated using transmission electron microscopy (TEM). It is shown that the Ni …
Electrochemical Performances Of Layered Polypyrrole/Chemically Reduced Graphene Oxide Nanocomposites As Supercapacitor Electrodes,
2012
Research Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University. Shanghai 200240,China
Electrochemical Performances Of Layered Polypyrrole/Chemically Reduced Graphene Oxide Nanocomposites As Supercapacitor Electrodes, Si-Zhe Xu, Xue-Jiao Zhou, Kun Wu, Yong-Qiang Yang, Hai-Xia Wu
Journal of Electrochemistry
Nanocomposites of polypyrrole (Ppy) and chemically reduced graphene oxide (CRGO), Ppy/CRGO, have been fabricated through in-situ polymerization of pyrrole on graphene oxide (GO) sheets. The as-synthesized Ppy/CRGO composites were characterized complementarily using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier transformed infrared spectroscopy (FT-IR). By controlling the initial ratio of the GO to pyrrole, the layered composites could be obtained and their thickness could be tuned properly. The Ppy/CRGO electrodes were prepared using a mechanical compressing technique and their electrical conductivity and electrochemical properties were characterized systematically. We demonstrated that as electrodes for supercapacitor, the Ppy/CRGO composites with Ppy …
Electrochemical Corrosion And Protection Of Copper Foil Treated By Surface Siloxane Filming,
2012
Department of Chemistry, Nanchang University, Nanchang 330031, China
Electrochemical Corrosion And Protection Of Copper Foil Treated By Surface Siloxane Filming, Wei-Jun Miao, Yu-Bao Zhang, Ning-Yu Gu, Feng Liu
Journal of Electrochemistry
Copper foil specimens were immersed in hydro-alcoholic solution of 3-amino-propyl-trimethoxy-silane (γ-APS) to prepare a protective self-assembled siloxane membrane on the surface. Potentiodynamic polarization and electrochemical impedance spectroscopic tests were performed in 0.1 mol.L-1 NaCl to evaluate the effects of the self-assembled siloxane membranes prepared at different pH of γ-APS on corrosion of copper foil. The surface morphology of siloxane membrane was studied by SEM. Experimental results revealed that the γ-APS self-assembled siloxane membranes effectively inhibited the corrosion of copper foil and the optimum anti-corrosion effect was found when the pH value of the silane solution was 7.
Electrochemical Sensing Of Guanine And Adenine Based On The Boron-Doped Carbon Nanotubes Modified Electrode,
2012
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
Electrochemical Sensing Of Guanine And Adenine Based On The Boron-Doped Carbon Nanotubes Modified Electrode, Ya-Lin Xia, Chun-Yan Deng, Juan Xiang
Journal of Electrochemistry
In this work, the boron-doped carbon nanotubes (BCNTs) modified glassy carbon (GC) electrode was simply fabricated, and the electrochemical oxidation behaviors of guanine and adenine at the BCNTs/GC electrode were investigated. Compared with the bare GC and CNTs/GC electrodes, the BCNTs-modified electrode exhibited extraordinary electrocatalytic activity towards the oxidations of guanine and adenine as indicated by the obvious increase in current responses. Moreover, the peak separation between guanine and adenine was large enough for their potential recognition in mixture without any separation or pretreatment. Therefore, the simultaneous determination of guanine and adenine was successfully achieved. The BCNTs/GC electrode showed high …
Direct Writing Of Au Nanoneedles Array On Glass By Confined Laser Spinning,
2012
Purdue University
Direct Writing Of Au Nanoneedles Array On Glass By Confined Laser Spinning, Yingling Yang, Dong Lin, Gary J. Cheng
Birck and NCN Publications
Generation of gold nanoneedles on glass by confined laser spinning was explored by using a nanosecond pulsed laser. When the coated Au thin film was irradiated under the confinement of glass, gold nanoneedles were formed by spreading the molten liquid of gold under high pressure. The mechanism of the confined laser spinning process is studied. The maximum velocity and instability of molten liquid during confined laser spinning were estimated. The diameter of nanoneedles can be controlled by changing the thickness of coated gold thin film. Large scale of gold nanoneedles can be formed by this direct writing method and collected …
Control Of Reflectance And Transmittance In Scattering And Curvilinear Hyperbolic Metamaterials,
2012
Norfolk State University
Control Of Reflectance And Transmittance In Scattering And Curvilinear Hyperbolic Metamaterials, T. U. Tumkur, J. K. Kitur, B. Chu, Lei Gu, V. A. Podolskiy, Evgenii E. Narimanov, M. A. Noginov
Birck and NCN Publications
We demonstrate reduced reflectance in curvilinear lamellar hyperbolic metamaterials as well as planar hyperbolic metamaterials consisting of metal/dielectric multilayers, with scatterers deposited on the top. The reduced reflectance is accompanied by a significant enhancement in transmission along with non-reciprocity of transmittance in forward and backward propagating directions. The observed experimental behavior is qualitatively similar to the results of numerical solutions of Maxwell equations. The findings of this study pave the way to a variety of important applications, including broadband enhancement of light trapping in photovoltaic devices. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4746387]
Multipartite Quantum Entanglement Evolution In Photosynthetic Complexes,
2012
Birck Nanotechnology Center, Purdue University
Multipartite Quantum Entanglement Evolution In Photosynthetic Complexes, Jing Zhu, Sabre Kais, Alan Aspuru-Guzik, Sam Rodriques, Ben Brock, Peter J. Love
Birck and NCN Publications
We investigate the evolution of entanglement in the Fenna-Matthew-Olson (FMO) complex based on simulations using the scaled hierarchical equations of motion approach. We examine the role of entanglement in the FMO complex by direct computation of the convex roof. We use monogamy to give a lower bound for entanglement and obtain an upper bound from the evaluation of the convex roof. Examination of bipartite measures for all possible bipartitions provides a complete picture of the multipartite entanglement. Our results support the hypothesis that entanglement is maximum primary along the two distinct electronic energy transfer pathways. In addition, we note that …
Electron Band Alignment At The Interface Of (100)Insb With Atomic-Layer Deposited Al2o3,
2012
Universite Catholique Louvain
Electron Band Alignment At The Interface Of (100)Insb With Atomic-Layer Deposited Al2o3, H.Y. Chou, V. V. Afanas'ev, M. Houssa, A. Stesmans, Lin Dong, Peide Ye
Birck and NCN Publications
From experiments on internal photoemission of electrons at the (100)InSb/Al2O3 interface, the top of the InSb valence band is found to be 3.05 +/- 0.10 eV below the oxide conduction band and corresponds to a conduction band offset of 2.9 +/- 0.1 eV. These results indicate that the top of valence band in InSb lies energetically at the same level as in GaSb and above the valence bands in InxGa1-xAs (0
Size-Dependent Hardness Of Nanoscale Metallic Contacts From Molecular Dynamics Simulations,
2012
Purdue University
Size-Dependent Hardness Of Nanoscale Metallic Contacts From Molecular Dynamics Simulations, Hojin Kim, Alejandro Strachan
Birck and NCN Publications
We characterize how size and shape affects the hardness of nanoscale metallic contacts using large-scale molecular dynamics (MD) simulations. High-aspect-ratio contacts continue the experimentally observed trend of hardening with decreasing contact size down to the sub-10-nm regime. However, we find that this effect is shape dependent and the rate of hardening with decreasing contact size diminishes as the aspect ratio of the asperities becomes smaller. Interestingly, low-aspect-ratio asperities that can support simple dislocation glide exhibit softening with decreasing size. A detailed analysis of the MD trajectories reveals the dislocation mechanisms that govern these complex size effects.
Shear-Horizontal Vibration Modes Of An Oblate Elliptical Cylinder And Energy Trapping In Contoured Acoustic Wave Resonators,
2012
University of Nebraska-Lincoln
Shear-Horizontal Vibration Modes Of An Oblate Elliptical Cylinder And Energy Trapping In Contoured Acoustic Wave Resonators, Huijing He, Jiashi Yang, John A. Kosinski
Department of Mechanical and Materials Engineering: Faculty Publications
We study shear-horizontal free vibrations of an elastic cylinder with an oblate elliptical cross section and a traction-free surface. Exact vibration modes and frequencies are obtained. The results show the existence of thickness-shear and thickness-twist modes. The energy-trapping behavior of these modes is examined. Trapped modes are found wherein the vibration energy is largely confined to the central portion of the cross section and little vibration energy is found at the edges. It is also shown that face-shear modes are not allowed in such a cylinder. The results are useful for the understanding of the energy trapping phenomenon in contoured …
Ultrastable Synergistic Tetravalent Rna Nanoparticles For Targeting To Cancers,
2012
University of Kentucky
Ultrastable Synergistic Tetravalent Rna Nanoparticles For Targeting To Cancers, Farzin Haque, Dan Shu, Yi Shu, Luda S. Shlyakhtenko, Piotr G. Rychahou, B. Mark Evers, Peixuan Guo
Pharmaceutical Sciences Faculty Publications
One of the advantages of nanotechnology is the feasibility to construct therapeutic particles carrying multiple therapeutics with defined structure and stoichiometry. The field of RNA nanotechnology is emerging. However, controlled assembly of stable RNA nanoparticles with multiple functionalities which retain their original role is challenging due to refolding after fusion. Herein, we report the construction of thermodynamically stable X-shaped RNA nanoparticles to carry four therapeutic RNA motifs by self-assembly of reengineered small RNA fragments. We proved that each arm of the four helices in the X-motif can harbor one siRNA, ribozyme, or aptamer without affecting the folding of the central …
An Extension To Particle Polarizability To Predict Coupling Behavior In Periodic Nanoplasmonic Arrays,
2012
University of Arkansas, Fayetteville
An Extension To Particle Polarizability To Predict Coupling Behavior In Periodic Nanoplasmonic Arrays, Drew Dejarnette
Graduate Theses and Dissertations
Plasmonic nanoparticles organized in arrays interact to create spectral patterns which are amplified by individual particle polarizability. It was hypothesized that particle polarizability could be used as a predictor of spectral behavior from far-field interactions within the array. Inter-particle coupling produced an extraordinary peak in extinction efficiency at wavelengths equal to or larger than the single particle plasmon resonance peak. Interactions that produced constructive coupling were found to mimic changes in the particle polarizability model. Testing of the hypothesis was performed using the coupled dipole approximation with parametric characterization of array geometries, giving specific particle size and lattice constant combinations …
Probing And Controlling Fluid Rheology At Microscale With Magnetic Nanorods,
2012
Clemson University
Probing And Controlling Fluid Rheology At Microscale With Magnetic Nanorods, Alexander Tokarev
All Dissertations
This Dissertation is focused on the development of new methods for characterization and control of fluid rheology using magnetic nanorods. This Dissertation consists of five chapters. In the first chapter, we review current microrheologial methods and develop a Magnetic Rotational Spectroscopy (MRS) model describing nanorod response to a rotating magnetic field. Using numerical modeling, we analyze the effects of materials parameters of nanorods and fluids on the MRS characteristic features. The model is designed for a specific experimental protocol. We introduce and examine physical parameters which can be measured experimentally. The model allows identification of MRS features enabling the calculation …
Component Mode Synthesis Approach For Quantum Mechanical Electrostatic And Transport Analysis Of Nanoscale Structures And Devices,
2012
Clemson University
Component Mode Synthesis Approach For Quantum Mechanical Electrostatic And Transport Analysis Of Nanoscale Structures And Devices, Zhe Gao
All Theses
As the dimensions of commonly used semiconductor devices have shrunk into nanometer regime, it is recognized that the influence of quantum effects on their electrostatic and transport properties cannot be ignored. In the past few decades, various computational models and approaches have been developed to analyze these properties in nanostructures and devices. Among these computational models, the Schršdinger-Poisson model has been widely adopted for quantum mechanical electrostatic and transport analysis of nanostructures and devices such as quantum wires, metal-oxide-semiconductor field effect transistors (MOSFETs) and nanoelectromechanical systems (NEMS). The numerical results allow for evaluations of the electrical properties such as charge …
Semiconductor Nanocrystals: From Quantum Dots To Quantum Disks,
2012
University of Arkansas, Fayetteville
Semiconductor Nanocrystals: From Quantum Dots To Quantum Disks, Zheng Li
Graduate Theses and Dissertations
The bottom-up colloidal synthesis opened up the possibility of finely tuning and tailoring the semiconductor nanocrystals. Numerous recipes were developed for the preparation of colloidal semiconductor nanocrystals, especially the traditional quantum dots. However, due to the lack of thorough understanding to those systems, the synthesis chemistry is still on the empirical level. CdS quantum dots synthesis in non-coordinating solvent were taken as a model system to investigate its molecular mechanism and formation process, ODE was identified as the reducing agent for the preparation of CdS nanocrystals, non-injection and low-temperature synthesis methods developed. In this model system, we not only proved …
Peptoid Based Slide Coatings For Disease Detection Via Elisa Microarray Analysis,
2012
University of Arkansas, Fayetteville
Peptoid Based Slide Coatings For Disease Detection Via Elisa Microarray Analysis, Melissa Lea Hebert
Graduate Theses and Dissertations
Poly-N-substituted glycines (peptoids) are a very versatile family of synthetic molecules that can be customized for any number of applications. In this study, we chose to use peptoids as a foundation for sandwich ELISA microarray analysis with a long term goal of creating an early detection device for complex diseases such as cancer. The peptoids were designed to self-assemble into microspheres to be used in coatings on the surface of the microarray substrates to increase the surface area available for antibody attachment. This increased antibody density would lead to an increase in the microarray analysis sensitivity and dynamic range. Studies …
Plasmonic Pervaporation Via Gold Nanoparticle-Functionalized Nanocomposite Membranes,
2012
University of Arkansas, Fayetteville
Plasmonic Pervaporation Via Gold Nanoparticle-Functionalized Nanocomposite Membranes, Aaron Russell
Graduate Theses and Dissertations
Butanol derived from biological feedstocks has significant potential as a liquid fuel source, but the separation methods used in its production can be prohibitively expensive and are therefore currently the subject of extensive research. Pervaporation is a promising membrane process that is effective in butanol separations, but involves a large energy demand. This study examines the possibility of increasing flux and energy efficiency in pervaporation via plasmonic heating of gold nanoparticle-functionalized, polymer nanocomposite membranes (AuNCMs) in lieu of conventional feed heating. An economic analysis demonstrated that plasmonic pervaporation could achieve significant reductions in energy usage and utility cost in butanol …
Fabrication And Characterization Of Thinner Solid-State Nanopores,
2012
University of Arkansas, Fayetteville
Fabrication And Characterization Of Thinner Solid-State Nanopores, Denis Forbi Tita
Graduate Theses and Dissertations
Solid State nanopores that are fabricated by the ion beam sculpting process and electron beam drilling have shown great promise as a sensing device for DNA and protein molecules. Even though biological pores such as the alpha-Haemolysin have been in use for quite some time, the use of solid state Nanopores in single biomolecule detection has been on the rise since the mid 1990s. Solid State nanopores have an advantage over biological pores in that they are more robust, stable, and can be sculpted to any desired size for use in translocation experiments. One of the major challenges in Nanopore …
Nanoscale Contacts Between Semiconducting Nanowires And Metallic Graphenes,
2012
Purdue University
Nanoscale Contacts Between Semiconducting Nanowires And Metallic Graphenes, Seongmin Kim, David B. Janes, Sung-Yool Choi, Sanghyun Ju
Birck and NCN Publications
Metal–semiconductor (M–S) junctions are important components in many semiconductor devices, and there is growing interest in realizing high quality M–S contacts that are optically transparent. In this paper, we present our investigations into the characteristics of M–S junction in a semiconducting ZnO nanowire that was directly grown on a multilayer graphene film (MGF). The synthesized nanowires were fabricated into two-terminal devices with MGF as one contact and Al as the other contact. By comparison with devices employing Al contacts at both ends, the nanowire resistivity and specific contact resistivity of the MGF–nanowire contact can be extracted. The extracted specific contact …
