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Electrodes

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Articles 1 - 30 of 90

Full-Text Articles in Physical Sciences and Mathematics

Development Of Antibacterial Neural Stimulation Electrodes Via Hierarchical Surface Restructuring And Atomic Layer Deposition., Henna Khosla, Wesley Seche, Daniel Ammerman, Sahar Elyahoodayan, Gregory A. Caputo, Jeffrey Hettinger, Shahram Amini, Gang Feng Nov 2023

Development Of Antibacterial Neural Stimulation Electrodes Via Hierarchical Surface Restructuring And Atomic Layer Deposition., Henna Khosla, Wesley Seche, Daniel Ammerman, Sahar Elyahoodayan, Gregory A. Caputo, Jeffrey Hettinger, Shahram Amini, Gang Feng

Faculty Scholarship for the College of Science & Mathematics

Miniaturization and electrochemical performance enhancement of electrodes and microelectrode arrays in emerging long-term implantable neural stimulation devices improves specificity, functionality, and performance of these devices. However, surgical site and post-implantation infections are amongst the most devastating complications after surgical procedures and implantations. Additionally, with the increased use of antibiotics, the threat of antibiotic resistance is significant and is increasingly being recognized as a global problem. Therefore, the need for alternative strategies to eliminate post-implantation infections and reduce antibiotic use has led to the development of medical devices with antibacterial properties. In this work, we report on the development of electrochemically …


Relevancy Of Pulsed Electroacoustic Measurements For Investigating Spacecraft Charging, Zachary Gibson, J. R. Dennison Feb 2023

Relevancy Of Pulsed Electroacoustic Measurements For Investigating Spacecraft Charging, Zachary Gibson, J. R. Dennison

Journal Articles

The magnitude and spatial distribution of charge embedded in dielectric materials and the evolution of the charge distributions with time are paramount for the understanding and mitigation of spacecraft charging. Spacecraft materials are charged primarily by incident fluxes of low-energy electrons, with electron fluxes in the 10–50 keV range often responsible for the most deleterious arcing effects. While the pulsed electroacoustic (PEA) method can provide sensitive nondestructive measurements of the internal charge distribution in insulating materials, it has often been limited for spacecraft charging applications by typical spatial resolutions of ≤ 10 μm , with a 10- μm …


Long-Range Aceo Phenomena In Microfluidic Channel, Diganta Dutta, Keifer Smith, Xavier Palmer Jan 2023

Long-Range Aceo Phenomena In Microfluidic Channel, Diganta Dutta, Keifer Smith, Xavier Palmer

Electrical & Computer Engineering Faculty Publications

Microfluidic devices are increasingly utilized in numerous industries, including that of medicine, for their abilities to pump and mix fluid at a microscale. Within these devices, microchannels paired with microelectrodes enable the mixing and transportation of ionized fluid. The ionization process charges the microchannel and manipulates the fluid with an electric field. Although complex in operation at the microscale, microchannels within microfluidic devices are easy to produce and economical. This paper uses simulations to convey helpful insights into the analysis of electrokinetic microfluidic device phenomena. The simulations in this paper use the Navier–Stokes and Poisson Nernst–Planck equations solved using COMSOL …


Infrared Spectra Of Small Radicals For Exoplanetary Spectroscopy: Oh, Nh, Cn, And Ch: The State Of Current Knowledge, Svatopluk Civiš, Adam Pastorek, Martin Ferus, Sergei N. Yurchenko, Noor-Ines Boudjema Jan 2023

Infrared Spectra Of Small Radicals For Exoplanetary Spectroscopy: Oh, Nh, Cn, And Ch: The State Of Current Knowledge, Svatopluk Civiš, Adam Pastorek, Martin Ferus, Sergei N. Yurchenko, Noor-Ines Boudjema

Chemistry & Biochemistry Faculty Publications

In this study, we present a current state-of-the-art review of middle-to-near IR emission spectra of four simple astrophysically relevant molecular radicals—OH, NH, CN and CH. The spectra of these radicals were measured by means of time-resolved Fourier transform infrared spectroscopy in the 700–7500 cm−1 spectral range and with 0.07–0.02 cm−1 spectral resolution. The radicals were generated in a glow discharge of gaseous mixtures in a specially designed discharge cell. The spectra of short-lived radicals published here are of great importance, especially for the detailed knowledge and study of the composition of exoplanetary atmospheres in selected new planets. Today, …


Long-Term Stability Of Ferri-/Ferrocyanide As An Electroactive Component For Redox Flow Battery Applications: On The Origin Of Apparent Capacity Fade, Eric M. Fell, Diana De Porcellinis, Yan Jing, Valeria Gutierrez-Venegas, Thomas Y. George, Roy G. Gordon, Sergio Granados-Focil, Michael Aziz Jan 2023

Long-Term Stability Of Ferri-/Ferrocyanide As An Electroactive Component For Redox Flow Battery Applications: On The Origin Of Apparent Capacity Fade, Eric M. Fell, Diana De Porcellinis, Yan Jing, Valeria Gutierrez-Venegas, Thomas Y. George, Roy G. Gordon, Sergio Granados-Focil, Michael Aziz

Chemistry

We assess the suitability of potassium ferri-/ferrocyanide as an electroactive species for long-term utilization in aqueous organic redox flow batteries. A series of electrochemical and chemical characterization experiments was performed to distinguish between structural decomposition and apparent capacity fade of ferri-/ferrocyanide solutions used in the capacity-limiting side of a flow battery. Our results indicate that, in contrast with previous reports, no structural decomposition of ferri-/ferrocyanide occurs at tested pH values as high as 14 in the dark or in diffuse indoor light. Instead, an apparent capacity fade takes place due to a chemical reduction of ferricyanide to ferrocyanide, via chemical …


Analysis Of Eeg Data Using Complex Geometric Structurization, Eddy A. Kwessi, L. J. Edwards Jul 2021

Analysis Of Eeg Data Using Complex Geometric Structurization, Eddy A. Kwessi, L. J. Edwards

Mathematics Faculty Research

Electroencephalogram (EEG) is a common tool used to understand brain activities. The data are typically obtained by placing electrodes at the surface of the scalp and recording the oscillations of currents passing through the electrodes. These oscillations can sometimes lead to various interpretations, depending on, for example, the subject’s health condition, the experiment carried out, the sensitivity of the tools used, or human manipulations. The data obtained over time can be considered a time series. There is evidence in the literature that epilepsy EEG data may be chaotic. Either way, the Embedding Theory in dynamical systems suggests that time series …


Supercapacitors With Gate Electrodes, Tazima Selim Chowdhury May 2019

Supercapacitors With Gate Electrodes, Tazima Selim Chowdhury

Dissertations

A new approach to improve the capacitance of supercapacitors (SC) is proposed in this study. A typical SC is composed of an anode and a cathode; a separator in between them assures an unintentional discharge of the capacitor. The study focuses on a family of structured separators, either electronically active or passive which are called gates. An active structured separator layer has been fabricated and analyzed. The structured separator has characteristics of electrical diode and is fabricated out of functionalized carbon nanotubes (CNT). Improvement of the overall capacitance of SC, equipped with either active or passive structured separators demonstrated a …


Manufacturing And Testing The Permanent Magnet Linear Motor, Renjie Kang May 2019

Manufacturing And Testing The Permanent Magnet Linear Motor, Renjie Kang

Senior Theses

Controlled mechanical motion is vital in many useful applications in technology. Among them, linear motors have advantages over traditional rotating motors. In this work, we built a permanent magnet linear motor to test and measure its energy efficiency. A maximum 29% total energy efficiency, and 67% energy transfer rate, were detected. In addition, a C-shape support structure was added to the moving part in order to increase the moving accuracy. The tests show that, with the support structure, the fluctuation in the vertical direction decreases significantly, but the friction of the system slightly increases.


A Simple And Robust Approach To Reducing Contact Resistance In Organic Transistors, Zachary A. Lamport, Katrina J. Barth, Hyunsu Lee, Eliot Gann, Sebastian Engmann, Hu Chen, Martin Guthold, Iain Mcculloch, John E. Anthony, Lee J. Richter, Dean M. Delongchamp, Oana D. Jurchescu Dec 2018

A Simple And Robust Approach To Reducing Contact Resistance In Organic Transistors, Zachary A. Lamport, Katrina J. Barth, Hyunsu Lee, Eliot Gann, Sebastian Engmann, Hu Chen, Martin Guthold, Iain Mcculloch, John E. Anthony, Lee J. Richter, Dean M. Delongchamp, Oana D. Jurchescu

Chemistry Faculty Publications

Efficient injection of charge carriers from the contacts into the semiconductor layer is crucial for achieving high-performance organic devices. The potential drop necessary to accomplish this process yields a resistance associated with the contacts, namely the contact resistance. A large contact resistance can limit the operation of devices and even lead to inaccuracies in the extraction of the device parameters. Here, we demonstrate a simple and efficient strategy for reducing the contact resistance in organic thin-film transistors by more than an order of magnitude by creating high work function domains at the surface of the injecting electrodes to promote channels …


Electrostatic Design And Conditioning Of A Triple Point Junction Shield For A −200 Kv Dc High Voltage Photogun, G. Palacios-Serrano, F. Hannon, C. Hernandez-Garcia, M. Poelker, H. Baumgart Oct 2018

Electrostatic Design And Conditioning Of A Triple Point Junction Shield For A −200 Kv Dc High Voltage Photogun, G. Palacios-Serrano, F. Hannon, C. Hernandez-Garcia, M. Poelker, H. Baumgart

Electrical & Computer Engineering Faculty Publications

Nuclear physics experiments performed at the Continuous Electron Beam Accelerator Facility (CEBAF) at the Jefferson Lab require a DC high voltage photogun to generate polarized electron beams from GaAs photocathodes. The photogun uses a tapered ceramic insulator that extends into the vacuum chamber and mechanically holds the cathode electrode. Increasing the operating voltage from nominal −130 kV to −200 kV will provide lower beam emittance, better transmission through injector apertures, and improved photocathode lifetime. This desire to increase the photogun operating voltage led to the design of a triple-point-junction shield electrode which minimizes the electric field at the delicate insulator-metal-vacuum …


Resonant Tunneling Across A Ferroelectric Domain Wall, M. Li, L. L. Tao, J. P. Velev, Evgeny Y. Tsymbal Apr 2018

Resonant Tunneling Across A Ferroelectric Domain Wall, M. Li, L. L. Tao, J. P. Velev, Evgeny Y. Tsymbal

Evgeny Tsymbal Publications

Motivated by recent experimental observations, we explore electron transport properties of a ferroelectric tunnel junction (FTJ) with an embedded head-to-head ferroelectric domain wall, using first-principles density-functional theory calculations. We consider a FTJ with La0.5Sr0.5MnO3 electrodes separated by a BaTiO3 barrier layer and show that an in-plane charged domain wall in the ferroelectric BaTiO3 can be induced by polar interfaces. The resulting V-shaped electrostatic potential profile across the BaTiO3 layer creates a quantum well and leads to the formation of a two-dimensional electron gas, which stabilizes the domain wall. The confined electronic states …


Chemically Stable Artificial Sei For Li-Ion Battery Electrodes, Qinglin Zhang, Lei Han, Jie Pan, Zhi Chen, Yang-Tse Cheng Mar 2017

Chemically Stable Artificial Sei For Li-Ion Battery Electrodes, Qinglin Zhang, Lei Han, Jie Pan, Zhi Chen, Yang-Tse Cheng

Chemical and Materials Engineering Faculty Publications

The importance of coating's chemical stability in lithium-ion batteries has been demonstrated by this study. It is well known that the mechanical properties determine the cycle life, and chemical stability or chemical degradation rate determines the calendar life. In this study, we used HfO2 coatings prepared by atomic layer deposition as an example to show the chemical stability of the coatings for lithium ion battery electrodes.


Incorporating A Spatial Prior Into Nonlinear D-Bar Eit Imaging For Complex Admittivities, Sarah J. Hamilton, Jennifer L. Mueller, Melody Alsaker Feb 2017

Incorporating A Spatial Prior Into Nonlinear D-Bar Eit Imaging For Complex Admittivities, Sarah J. Hamilton, Jennifer L. Mueller, Melody Alsaker

Mathematics, Statistics and Computer Science Faculty Research and Publications

Electrical Impedance Tomography (EIT) aims to recover the internal conductivity and permittivity distributions of a body from electrical measurements taken on electrodes on the surface of the body. The reconstruction task is a severely ill-posed nonlinear inverse problem that is highly sensitive to measurement noise and modeling errors. Regularized D-bar methods have shown great promise in producing noise-robust algorithms by employing a low-pass filtering of nonlinear (nonphysical) Fourier transform data specific to the EIT problem. Including prior data with the approximate locations of major organ boundaries in the scattering transform provides a means of extending the radius of the low-pass …


Beyond The Point Charge: Equipotential Surfaces And Electric Fields Of Various Charge Configurations, Jeffrey A. Phillips, Jeff Sanny, David Berube, Anatol Hoemke Jan 2017

Beyond The Point Charge: Equipotential Surfaces And Electric Fields Of Various Charge Configurations, Jeffrey A. Phillips, Jeff Sanny, David Berube, Anatol Hoemke

Physics Faculty Works

A laboratory experiment often performed in an introductory electricity and magnetism course involves the mapping of equipotential lines on a conductive sheet between two objects at different potentials. In this article, we describe how we have expanded this experiment so that it can be used to illustrate the electrostatic properties of conductors. Different configurations of electrodes can be used to show that the electric field is zero inside a conductor as well as within a cavity, the electric field is perpendicular to conducting surfaces, and the charge distribution on conducting surfaces can vary.


Flexible Polycaprolactone (Pcl) Supercapacitor Based On Reduced Graphene Oxide (Rgo)/Single-Wall Carbon Nanotubes (Swnts) Composite Electrodes, Hyeon Taek Jeong, Yong-Ryeol Kim, Byung Chul Kim Jan 2017

Flexible Polycaprolactone (Pcl) Supercapacitor Based On Reduced Graphene Oxide (Rgo)/Single-Wall Carbon Nanotubes (Swnts) Composite Electrodes, Hyeon Taek Jeong, Yong-Ryeol Kim, Byung Chul Kim

Australian Institute for Innovative Materials - Papers

The reduced graphene oxide (rGO)/single-wall carbon nanotubes (SWNTs) composites are coated onto the polycaprolactone (PCL) substrate via spray coating technique to prepare a flexible supercapacitor. The electrochemical properties of the flexible PCL supercapacitor as a function of bending cycles and angles are evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge tests. The EIS and charge/discharge curves of the flexible PCL supercapacitor exhibit capacitive behavior even after prolonged bending cycles up to 500. The highest capacitance value of the unbent PCL supercapacitor is 52.5 F g-1 which retained 65% after 500 bending with 6000th galvanostatic charge/discharge cycles.


The Relationship Between Time Of Day, Mood, And Electroencephalography (Eeg) Asymmetry, Morgan Tantillo May 2016

The Relationship Between Time Of Day, Mood, And Electroencephalography (Eeg) Asymmetry, Morgan Tantillo

Honors Projects

Previous researchers have had success in finding a correlation between exercise and an increase in positive mood. Researchers have also found a correlation between time of day and mood. The current study will explore the relationship between time of day, mood, and electroencephalography (EEG) asymmetry. The study utilized a convenient sample of ten undergraduate students at Bowling Green State University. Participants had baseline EEG recordings taken, and then participated in moderate exercise, followed by another EEG recording. Participants’ mood was assessed through a self-reported mood questionnaire before the condition as well as immediately after. Due to multiple statistical tests, the …


Ambient Synthesis Of One-/Two-Dimensional Cuagse Ternary Nanotubes As Counter Electrodes Of Quantum-Dot-Sensitized Solar Cells, Xin Qi Chen, Yang Bai, Zhen Li, Lian Zhou Wang, S X. Dou Jan 2016

Ambient Synthesis Of One-/Two-Dimensional Cuagse Ternary Nanotubes As Counter Electrodes Of Quantum-Dot-Sensitized Solar Cells, Xin Qi Chen, Yang Bai, Zhen Li, Lian Zhou Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. One-/two-dimensional ternary CuAgSe nanotubes (NTs) were successfully prepared from copper selenide (Cu2-xSe) NTs at room temperature within a short reaction time by the facile cation-exchange approach. Cation exchange leads to the transformation of the crystal structure from cubic into orthorhombic and/or tetragonal with good retention of morphology. The exchange reactions are spontaneous owing to large negative changes of the Gibbs free energy. The effects of parameters such as reaction time, precursor source, and precursor ratio on the exchange reaction were investigated. The resultant CuAgSe NTs were explored as counter electrodes (CEs) of …


Nitrogen-Doped Graphene Ribbon Assembled Core-Sheath Mno@Graphene Scrolls As Hierarchically Ordered 3d Porous Electrodes For Fast And Durable Lithium Storage, Yun Zhang, Penghui Chen, Xu Gao, Bo Wang, Heng Liu, Haobin Wu, Hua-Kun Liu, Shi Xue Dou Jan 2016

Nitrogen-Doped Graphene Ribbon Assembled Core-Sheath Mno@Graphene Scrolls As Hierarchically Ordered 3d Porous Electrodes For Fast And Durable Lithium Storage, Yun Zhang, Penghui Chen, Xu Gao, Bo Wang, Heng Liu, Haobin Wu, Hua-Kun Liu, Shi Xue Dou

Australian Institute for Innovative Materials - Papers

Graphene scroll is an emerging 1D tubular form of graphitic carbon that has potential applications in electrochemical energy storage. However, it still remains a challenge to composite graphene scrolls with other nanomaterials for building advanced electrode configuration with fast and durable lithium storage properties. Here, a transition-metal-oxide-based hierarchically ordered 3D porous electrode is designed based on assembling 1D core-sheath MnO@N-doped graphene scrolls with 2D N-doped graphene ribbons. In the resulting architecture, porous MnO nanowires confined in tubular graphene scrolls are mechanically isolated but electronically wellconnected, while the interwoven graphene ribbons offer continuous conductive paths for electron transfer in all directions. …


Expeditious And Eco-Friendly Hydrothermal Polymerization Of Pedot Nanoparticles For Binderfree High Performance Supercapacitor Electrodes, Murugesan Rajesh, C Justin Raj, Byung Chul Kim, Ramu Manikandan, Sung Jin Kim, Sang-Yeup Prof Sang-Yeup Park, Kwangsoo Lee, Kook Hyun Yu Jan 2016

Expeditious And Eco-Friendly Hydrothermal Polymerization Of Pedot Nanoparticles For Binderfree High Performance Supercapacitor Electrodes, Murugesan Rajesh, C Justin Raj, Byung Chul Kim, Ramu Manikandan, Sung Jin Kim, Sang-Yeup Prof Sang-Yeup Park, Kwangsoo Lee, Kook Hyun Yu

Australian Institute for Innovative Materials - Papers

Poly(3,4-ethylenedioxythiophene) (PEDOT) is a promising conjugated polymer that has attracted attention because of its outstanding electronic properties, useful for a wide range of applications in energy storage devices. However, synthesis of high-quality PEDOT occurs via vapour phase polymerization and chemical vapour deposition techniques using extrinsic hard templates or complicated experimental setups. This study introduces a simple hydrothermal polymerization technique using ferric chloride (FeCl3) as an oxidizing agent to overcome the above drawback, which results in good conductive, crystalline PEDOT nanodendrites and nanospheres. The effects of varying the molar ratio of FeCl3 oxidant were investigated in terms of the structural, morphological …


Effective Area And Charge Density Of Chondroitin Sulphate Doped Pedot Modified Electrodes, Alexander R. Harris, Paul J. Molino, Antonio G. Paolini, Gordon G. Wallace Jan 2016

Effective Area And Charge Density Of Chondroitin Sulphate Doped Pedot Modified Electrodes, Alexander R. Harris, Paul J. Molino, Antonio G. Paolini, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Neural electrodes have been coated with electrodeposited poly-3,4-ethylenedioxythiophene doped with chondroitin sulphate. Optical and electrochemical methods were used to determine the effective electrode area, charge injection capacity and charge density of the modified electrodes. Deposition times of 15 to 60 s slightly increased the geometric and steady state diffusion electroactive areas while the linear diffusion electroactive area grew significantly, indicating an increase in electrode roughness. The effective electrode area and charge injection capacity were significantly smaller than PEDOT doped with previously tested dopants. In contrast to other dopant ions, the charge density determined from the geometric and steady state diffusion …


Ultrathin Porous Nio Nanoflake Arrays On Nickel Foam As Binder-Free Electrodes For Supercapacitors, Qing Liu, Qinglong Yan, Shuang Wu, Jieqiang Wang, Hua-Kun Liu Jan 2016

Ultrathin Porous Nio Nanoflake Arrays On Nickel Foam As Binder-Free Electrodes For Supercapacitors, Qing Liu, Qinglong Yan, Shuang Wu, Jieqiang Wang, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

NiO nanopowders and NiO/nickel foam (NF) hybrid were synthesized by microwave hydrothermal method and the following heating process. NiO nanopowders show the morphology of microspheres (diameter is about 3μm), which are composed of porous nanoflakes. NiO/NF hybrid shows a porous nanoflakes array structure, the thickness of nanoflakes is 10nm. Electrochemical measurements indicate that the maximum specific capacitance of NiO nanopowders is about 85.4 F/g at a scan rate of 5 mV/s, while this value is up to 234.8 F/g for NiO/NF hybrid. Electrochemical impedance spectrum (EIS) data show that the Rs and Rct values of NiO/NF hybrid (1.9Ù and 0.25Ù) …


Correlation Of Impedance And Effective Electrode Area Of Dextran Sulfate Doped Pedot Modified Electrodes, Alexander R. Harris, Robyn C. Hutchinson, Paul J. Molino, Robert M. I Kapsa, Graeme M. Clark, Antonio G. Paolini, Gordon G. Wallace Jan 2016

Correlation Of Impedance And Effective Electrode Area Of Dextran Sulfate Doped Pedot Modified Electrodes, Alexander R. Harris, Robyn C. Hutchinson, Paul J. Molino, Robert M. I Kapsa, Graeme M. Clark, Antonio G. Paolini, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The impedance of electrodes at 1 kHz is typically reported to assess the signal-to-noise ratio of neural recording electrodes. The impedance response of platinum electrodes modified by poly-3,4-ethylenedioxythiophene doped with dextran sulfate has been examined. The modified electrodes have lower impedance at low and intermediate frequencies compared to unmodified electrodes. The impedance and phase angle at low frequencies is strongly correlated with the electrode area. The geometric and linear diffusion charge densities of the modified electrodes are also dependent on the electrode area and impedance at low frequencies. A 3 time constant equivalent circuit provided a better fit to the …


3d Binder-Free Mose2 Nanosheets/Carbon Cloth Electrodes For Efficient And Stable Hydrogen Evolution Prepared By Simple Electrophoresis Deposition Strategy, Yundan Liu, Long Ren, Zhen Zhang, Xiang Qi, Hongxing Li, Jianxin Zhong Jan 2016

3d Binder-Free Mose2 Nanosheets/Carbon Cloth Electrodes For Efficient And Stable Hydrogen Evolution Prepared By Simple Electrophoresis Deposition Strategy, Yundan Liu, Long Ren, Zhen Zhang, Xiang Qi, Hongxing Li, Jianxin Zhong

Australian Institute for Innovative Materials - Papers

We successfully developed a simple electrophoretic deposition (EPD) method to decorate the MoSe2 nanosheets on the carbon fiber surface of carbon cloth (MoSe2/CC). With this process, MoSe2 nanosheets can be uniformly and tightly deposited on this flexible conductor to form a 3D binder-free electrode for hydrogen evolution reaction (HER). The film thickness can also be controlled by the EPD time. Directly used as binder-free electrodes for hydrogen evolution reaction, the as-prepared 3D MoSe2/CC samples exhibit excellent catalytic activity in an acidic electrolyte (21 mA/cm2 at an over-potential of 250 mV). Variation of MoSe2 nanosheets film thickness in the electrodes could …


Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace Jun 2015

Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace

Robert Gorkin III

In this report single-wall carbon nanotubes (SWNTs) were coated onto latex using spray coating to produce a stretchable electrode. The electrochemical properties of the electrode were determined using cyclic voltammetry and electrochemical impedance spectroscopy and galvanostatic charge/discharge tests were also carried out. The impedance and charge/discharge curves of the latex/SWNTs electrode showed good capacitive behavior even after repetitive stretching to 100% strain. The highest capacitance value obtained for the unstretched SWNTs electrode was 119 F g−1 in 1 M Na2SO4 at 5 mV s−1. After the 100th stretch ≈ 80% of the original capacitance value was retained.


Three Dimensional (3d) Printed Electrodes For Interdigitated Supercapacitors, Chen Zhao, Caiyun Wang, Robert Gorkin Iii, Stephen Beirne, Kewei Shu, Gordon Wallace Jun 2015

Three Dimensional (3d) Printed Electrodes For Interdigitated Supercapacitors, Chen Zhao, Caiyun Wang, Robert Gorkin Iii, Stephen Beirne, Kewei Shu, Gordon Wallace

Robert Gorkin III

Common fabrication techniques typically require multiple and complex MEMS processing steps to create 3D electrode architectures. Here we report on the use of Additive Fabrication metal printing based on Selective Laser Melting (SLM) technology to produce 3D titanium interdigitated electrodes. This was used as a platform to deposit polypyrrole and the resultant structure was evaluated for use as a capacitive electrode. We also demonstrate a solid-state interdigitated supercapacitor using a poly(vinyl alcohol) (PVA)-H3PO4 polymer electrolyte.


Fabricating Electrodes For Amperometric Detection In Hybrid Paper/Polymer Lab-On-A-Chip Devices, Neus Godino, Robert Gorkin Iii, Ken Bourke, Jens Ducree Jun 2015

Fabricating Electrodes For Amperometric Detection In Hybrid Paper/Polymer Lab-On-A-Chip Devices, Neus Godino, Robert Gorkin Iii, Ken Bourke, Jens Ducree

Robert Gorkin III

We present a novel, low-resource fabrication and assembly method for creating disposable amperometric detectors in hybrid paper-polymer devices. Currently, mere paper-based microfluidics is far from being able to achieve the same level of process control and integration as state-of-the-art microfluidic devices made of polymers. To overcome this limitation, in this work both substrate types are synergistically combined through a hybrid, multi-component/multi-material system assembly. Using established inkjet wax printing, we transform the paper into a profoundly hydrophobic substrate in order to create carbon electrodes which are simply patterned from carbon inks via custom made adhesive stencils. By virtue of the compressibility …


Growth Of Ordered Nanostructure Arrays Including Nanotubes And Nanorods For High Efficiency Solar Cells, Wipula P. Liyanage, Manashi Nath May 2015

Growth Of Ordered Nanostructure Arrays Including Nanotubes And Nanorods For High Efficiency Solar Cells, Wipula P. Liyanage, Manashi Nath

Chemistry Faculty Research & Creative Works

A simple and straightforward approach has been described for the fabrication of CdTe nanotube and nanorod arrays with a high degree of precision through confined electrodeposition on lithographically patterned nanoelectrodes. This technique has the potential of growing these nanotube/nanowire arrays with extreme uniformity over a significantly large area. the desired nanoelectrode pattern was defined through electron beam lithography on indium tin oxide coated glass, and electrodeposition of the semiconducting material of interest (CdTe) on the nanoelecrodes produced the nanotubes/nanowires. It is interesting to note that the measured photocurrent density of nanotube device created by this protocol exceeds that obtained from …


Reduced Graphene Oxide And Polypyrrole/Reduced Graphene Oxide Composite Coated Stretchable Fabric Electrodes For Supercapacitor Application, Chen Zhao, Kewei Shu, Caiyun Wang, Sanjeev Gambhir, Gordon G. Wallace Jan 2015

Reduced Graphene Oxide And Polypyrrole/Reduced Graphene Oxide Composite Coated Stretchable Fabric Electrodes For Supercapacitor Application, Chen Zhao, Kewei Shu, Caiyun Wang, Sanjeev Gambhir, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The advent of self-powered functional garments has given rise to a demand for stretchable energy storage devices that are amendable to integration into textile structures. The electromaterials (anode, cathode and separator) are expected to sustain a deformation of 3% to 55% associated with body movement. Here, we report a stretchable fabric supercapacitor electrode using commonly available nylon lycra fabric as the substrate and graphene oxide (GO) as a dyestuff. It was prepared via a facile dyeing approach followed by a mild chemical reduction. This reduced graphene oxide (rGO) coated fabric electrode retains conductivity at an applied strain of up to …


In Situ Anchoring Uniform Mno2 Nanosheets On Three-Dimensional Macroporous Graphene Thin-Films For Supercapacitor Electrodes, Yong Zhao, Yuena Meng, Haiping Wu, Yue Wang, Zhixiang Wei, Xiaojun Li, Peng Jiang Jan 2015

In Situ Anchoring Uniform Mno2 Nanosheets On Three-Dimensional Macroporous Graphene Thin-Films For Supercapacitor Electrodes, Yong Zhao, Yuena Meng, Haiping Wu, Yue Wang, Zhixiang Wei, Xiaojun Li, Peng Jiang

Australian Institute for Innovative Materials - Papers

We present a facile and efficient fabrication of 3D macroporous rGO/MnO2 nanosheet thin-films for supercapacitor electrodes. An amorphous-carbon-modified rGO thin-film is firstly prepared through a simple glucose and CaCO3 particle mediated template method. Then ultrathin MnO2 nanosheets are in situ synthesized on the rGO networks by the rapid and scalable redox reaction between KMnO4 and amorphous carbon. The fabricated three-dimensional porous hybrid thin-film shows a high specific capacitance of 245 F g-1 (based on the total mass of the film) at a scan rate of 2 mV s-1, a good rate capability of 143 F g-1 at 300 mV s-1, …


Surface Engineering And Design Strategy For Surface-Amorphized Tio 2 @Graphene Hybrids For High Power Li-Ion Battery Electrodes, Tengfei Zhou, Yang Zheng, Hong Gao, Shudi Min, Sean Li, Hua-Kun Liu, Zaiping Guo Jan 2015

Surface Engineering And Design Strategy For Surface-Amorphized Tio 2 @Graphene Hybrids For High Power Li-Ion Battery Electrodes, Tengfei Zhou, Yang Zheng, Hong Gao, Shudi Min, Sean Li, Hua-Kun Liu, Zaiping Guo

Australian Institute for Innovative Materials - Papers

Electrode materials with battery-like high capacity and capacitorlike rate performance are highly desirable, since they would signifi cantly advance next-generation energy storage technology. [ 1 ] TiO 2 has received increasing attention as an anode material for lithium-ion batteries (LIBs) due to its good reversible capacity and low volume expansion upon lithiation, as well as its low cost and safe lithiation potential. [ 2 ] The low lithium-ion mobility within the crystalline phase TiO 2 , however, together with its poor electrical conductivity, means that only a thin surface layer of the host material is available for Li intercalation at …