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Full-Text Articles in Physical Sciences and Mathematics

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.


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 …


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 …


Soft, Flexible Freestanding Neural Stimulation And Recording Electrodes Fabricated From Reduced Graphene Oxide, Nicholas V. Apollo, Matias I. Maturana, Wei Tong, David A. X Nayagam, Mohit N. Shivdasani, Javad Foroughi, Gordon G. Wallace, Steven Prawer, Michael R. Ibbotson, David J. Garrett Jan 2015

Soft, Flexible Freestanding Neural Stimulation And Recording Electrodes Fabricated From Reduced Graphene Oxide, Nicholas V. Apollo, Matias I. Maturana, Wei Tong, David A. X Nayagam, Mohit N. Shivdasani, Javad Foroughi, Gordon G. Wallace, Steven Prawer, Michael R. Ibbotson, David J. Garrett

Australian Institute for Innovative Materials - Papers

There is an urgent need for conductive neural interfacing materials that exhibit mechanically compliant properties, while also retaining high strength and durability under physiological conditions. Currently, implantable electrode systems designed to stimulate and record neural activity are composed of rigid materials such as crystalline silicon and noble metals. While these materials are strong and chemically stable, their intrinsic stiffness and density induce glial scarring and eventual loss of electrode function in vivo. Conductive composites, such as polymers and hydrogels, have excellent electrochemical and mechanical properties, but are electrodeposited onto rigid and dense metallic substrates. In the work described here, strong …


Nano-Carbon Electrodes For Thermal Energy Harvesting, Mark S. Romano, Joselito M. Razal, Dennis Antiohos, Gordon G. Wallace, Jun Chen Jan 2015

Nano-Carbon Electrodes For Thermal Energy Harvesting, Mark S. Romano, Joselito M. Razal, Dennis Antiohos, Gordon G. Wallace, Jun Chen

Australian Institute for Innovative Materials - Papers

Thermogalvanic cells are capable of converting waste heat (generated as a by-product of almost all human activity) to electricity. These devices may alleviate the problems associated with the use of fossil fuels to meet the world's current demand for energy. This review discusses the developments in thermogalvanic systems attained through the use of nano-carbons as the electrode materials. Advances in cell design and electrode configuration that improve performance of these thermo converters and make them applicable in a variety of environments are also summarized. It is the aim of this review to act as a channel for further developments in …


Flexible Electrodes And Electrolytes For Energy Storage, Caiyun Wang, Gordon G. Wallace Jan 2015

Flexible Electrodes And Electrolytes For Energy Storage, Caiyun Wang, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The advent of flexible, wearable electronics has placed new demands on energy storage systems. The demands for high energy density achieved through the use of highly conducting materials with high surface area that enable facile electrochemical processes must now be coupled with the need for robustness and flexibility in each of the components: electrodes and electrolytes. This perspective provides an overview of materials and fabrication protocols used to produce flexible electrodes and electrolytes. We also discuss the key challenges in the development of high performance flexible energy storage devices. Only selected references are used to illustrate the myriad of developments …


Optical And Electrochemical Methods For Determining The Effective Area And Charge Density Of Conducting Polymer Modified Electrodes For Neural Stimulation, Alexander R. Harris, Paul Molino, Robert M. I Kapsa, Graeme M. Clarke, Antonio Paolini, Gordon G. Wallace Jan 2014

Optical And Electrochemical Methods For Determining The Effective Area And Charge Density Of Conducting Polymer Modified Electrodes For Neural Stimulation, Alexander R. Harris, Paul Molino, Robert M. I Kapsa, Graeme M. Clarke, Antonio Paolini, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Neural stimulation is used in the cochlear implant, bionic eye, and deep brain stimulation, which involves implantation of an array of electrodes into a patient's brain. The current passed through the electrodes is used to provide sensory queues or reduce symptoms associated with movement disorders and increasingly for psychological and pain therapies. Poor control of electrode properties can lead to suboptimal performance; however, there are currently no standard methods to assess them, including the electrode area and charge density. Here we demonstrate optical and electrochemical methods for measuring these electrode properties and show the charge density is dependent on electrode …


Liquid Crystalline Graphene Oxide/Pedot: Pss Self-Assembled 3d Architecture For Binder-Free Supercapacitor Electrodes, Md. Monirul Islam, Alfred T. Chidembo, Seyed Hamed Aboutalebi, Dean Cardillo, Hua-Kun Liu, Konstantin K. Konstantinov, S X. Dou Jan 2014

Liquid Crystalline Graphene Oxide/Pedot: Pss Self-Assembled 3d Architecture For Binder-Free Supercapacitor Electrodes, Md. Monirul Islam, Alfred T. Chidembo, Seyed Hamed Aboutalebi, Dean Cardillo, Hua-Kun Liu, Konstantin K. Konstantinov, S X. Dou

Australian Institute for Innovative Materials - Papers

Binder-free self-assembled 3D architecture electrodes have been fabricated by a novel convenient method. Liquid crystalline graphene oxide was used as precursor to interact with poly(3,4-ethylene-dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) in dispersion in order to form a conductive polymer entrapped, self-assembled layer-by-layer structure. This advanced network containing PEDOT:PSS enabled us to ascribe the superior electrochemical properties of particular graphene sheets. This layer-by-layer self-assembled 3D architecture of best performing composite (reduced graphene oxide-PEDOT:PSS 25) showed excellent electrochemical performance of 434 F g−1 through chemical treatment. To highlight these advances, we further explored the practicality of the as-prepared electrode by varying the composite material content. …


Three Dimensional (3d) Printed Electrodes For Interdigitated Supercapacitors, Chen Zhao, Caiyun Wang, Robert Gorkin Iii, Stephen Beirne, Kewei Shu, Gordon G. Wallace Jan 2014

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

Australian Institute for Innovative Materials - Papers

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.


Performance Enhancement Of Single-Walled Nanotube-Microwave Exfoliated Graphene Oxide Composite Electrodes Using A Stacked Electrode Configuration, Dennis Antiohos, Mark S. Romano, Joselito M. Razal, Stephen Beirne, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Jun Chen Jan 2014

Performance Enhancement Of Single-Walled Nanotube-Microwave Exfoliated Graphene Oxide Composite Electrodes Using A Stacked Electrode Configuration, Dennis Antiohos, Mark S. Romano, Joselito M. Razal, Stephen Beirne, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Jun Chen

Australian Institute for Innovative Materials - Papers

We report the development of a stacked electrode supercapacitor cell using stainless steel meshes as the current collectors and optimised single walled nanotubes (SWNT)-microwave exfoliated graphene oxide (mw rGO) composites as the electrode material. The introduction of mw rGO into a SWNT matrix creates an intertwined porous structure that enhances the electroactive surface area and capacitive performance due to the 3-D hierarchical structure that is formed. The composite structure was optimised by varying the weight ratio of the SWNTs and mw rGO. The best performing ratio was the 90% SWNT-10% mw rGO electrode which achieved a specific capacitance of 306 …


Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace Jan 2014

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

Australian Institute for Innovative Materials - Papers

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.


Highly Oriented Lifepo4 Thin Film Electrodes Via Chemical Solution Deposition, Qi Li, Shulei Chou, Jiazhao Wang, Dongqi Shi, Hua-Kun Liu Jan 2014

Highly Oriented Lifepo4 Thin Film Electrodes Via Chemical Solution Deposition, Qi Li, Shulei Chou, Jiazhao Wang, Dongqi Shi, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Highly oriented LiFePO4 thin-film electrodes were fabricated via chemical solution deposition combined with spin coating. The effects of the precursor concentrations and types of substrates on microstructures and electrochemical performances were studied. Single-phase LiFePO4 with orientations perpendicular to the (211)/(020) and (311) planes prepared using stainless steel as substrate presents the capacity of 4.9 μAh•cm-2 and the apparent activation energy of 59.2 kJ•mol-1, indicating its great potential to be used as cathode material for lithium thin film batteries.


A Method For Systematic Electrochemical And Electrophysiological Evaluation Of Neural Recording Electrodes, Alexander R. Harris, Simeon J. Morgan, Gordon G. Wallace, Antonio Paolini Jan 2014

A Method For Systematic Electrochemical And Electrophysiological Evaluation Of Neural Recording Electrodes, Alexander R. Harris, Simeon J. Morgan, Gordon G. Wallace, Antonio Paolini

Australian Institute for Innovative Materials - Papers

New materials and designs for neural implants are typically tested separately, with a demonstration of performance but without reference to other implant characteristics. This precludes a rational selection of a particular implant as optimal for a particular application and the development of new materials based on the most critical performance parameters. This article develops a protocol for in vitro and in vivo testing of neural recording electrodes. Recommended parameters for electrochemical and electrophysiological testing are documented with the key steps and potential issues discussed. This method eliminates or reduces the impact of many systematic errors present in simpler in vivo …


The Detailed Characterization Of Electrochemically Switchable Molecular Assemblies On Silicon Electrodes, Simone Ciampi, Michael James, Moinul H. Choudhury, Nadim A. Darwish, J Justin Gooding Jan 2013

The Detailed Characterization Of Electrochemically Switchable Molecular Assemblies On Silicon Electrodes, Simone Ciampi, Michael James, Moinul H. Choudhury, Nadim A. Darwish, J Justin Gooding

Australian Institute for Innovative Materials - Papers

In this paper we explore a multi-step synthetic strategy toward fabrication of monolayer-modified Si(100) electrodes that can be electrochemically switched. The synthetic scheme is modular and benefits from an established intramolecular lactonization scheme of benzoquinone analogs. A redox-tagged pendant group can be released from the surface such as to allow for in situ monitoring of the switch process. We show that this model system can be used to elucidate chemical and structural events for a surface dynamic system that is rapidly gaining popularity. The influence of polarization times, overpotentials and semiconductor doping type on the kinetic of the switch event …


Pegylation Of Platinum Bio-Electrodes, Zhilian Yue, Paul J. Molino, Xiao Liu, Gordon G. Wallace Jan 2013

Pegylation Of Platinum Bio-Electrodes, Zhilian Yue, Paul J. Molino, Xiao Liu, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Controlling protein interactions at the implanted electrode interface is becoming an important strategy for the management of foreign body responses that have proven to be detrimental to the long-term performance of neural prosthesis. In this study, PEGylation was conducted on platinum bio-electrodes to render the surface protein-resistant. The PEGylated electrode was investigated using a quartz crystal microbalance-dissipation, electrochemical impedance spectroscopy and cyclic voltammetiy.


Conducting Polymer Coated Neural Recording Electrodes, Alexander R. Harris, Simon Morgan, Jun Chen, Robert M. Kapsa, Gordon G. Wallace, Antonio Paolini Jan 2013

Conducting Polymer Coated Neural Recording Electrodes, Alexander R. Harris, Simon Morgan, Jun Chen, Robert M. Kapsa, Gordon G. Wallace, Antonio Paolini

Australian Institute for Innovative Materials - Papers

Neural recording electrodes suffer from poor signal to noise ratio, charge density, biostability and biocompatibility. This paper investigates the ability of conducting polymer coated electrodes to record acute neural response in a systematic manner, allowing in depth comparison of electrochemical and electrophysiological response. Approach. Polypyrrole (Ppy) and poly-3,4-ethylenedioxythiophene (PEDOT) doped with sulphate (SO4) or para-toluene sulfonate (pTS) were used to coat iridium neural recording electrodes. Detailed electrochemical and electrophysiological investigations were undertaken to compare the effect of these materials on acute in vivo recording. Main results. A range of charge density and impedance responses were seen with each respectively doped …


Facile Synthesis Of Reduced Graphene Oxide/Mwnts Nanocomposite Supercapacitor Materials Tested As Electrophoretically Deposited Films On Glassy Carbon Electrodes, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Byung C. Kim, Rao Yepuri, Anthony C. Romeo, Gordon G. Wallace Jan 2013

Facile Synthesis Of Reduced Graphene Oxide/Mwnts Nanocomposite Supercapacitor Materials Tested As Electrophoretically Deposited Films On Glassy Carbon Electrodes, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Byung C. Kim, Rao Yepuri, Anthony C. Romeo, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

This paper reports on a facile synthesis method for reduced graphene oxide (rGO)/multi-walled carbon nanotubes (MWNTs) nanocomposites. The initial step involves the use of graphene oxide to disperse the MWNTs, with subsequent reduction of the resultant graphene oxide/MWNTs composites using l-ascorbic acid (LAA) as a mild reductant. Reduction by LAA preserves the interaction between the rGO sheets and MWNTs. The dispersion-containing rGO/MWNTs composites was characterized and electrophoretically deposited anodically onto glassy carbon electrodes to form high surface area films for capacitance testing. Pseudo capacitance peaks were observed in the rGO/MWNTs composite electrodes, resulting in superior performance with capacitance values up …


Intrinsically Stretchable Supercapacitors Composed Of Polypyrrole Electrodes And Highly Stretchable Gel Electrolyte, Chen Zhao, Caiyun Wang, Zhilian Yue, Kewei Shu, Gordon G. Wallace Jan 2013

Intrinsically Stretchable Supercapacitors Composed Of Polypyrrole Electrodes And Highly Stretchable Gel Electrolyte, Chen Zhao, Caiyun Wang, Zhilian Yue, Kewei Shu, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

There has been an emerging interest in stretchable power sources compatible with flexible/wearable electronics. Such power sources must be able to withstand large mechanical strains and still maintain function. Here we report a highly stretchable H3PO4-poly(vinyl alcohol) (PVA) polymer electrolyte obtained by optimizing the polymer molecular weight and its weight ratio to H3PO4 in terms of conductivity and mechanical properties. The electrolyte demonstrates a high conductivity of 3.4 x 10-3 S cm-1, and a high fracture strain at 410% elongation. It is mechanically robust with a tensile strength of 2 MPa and a Young's modulus of 1 MPa, and displays …


Fabrication Of Graphene Electrodes By Electrophoretic Deposition And Their Synergistic Effects With Pedot And Platinum, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Gordon G. Wallace Jan 2013

Fabrication Of Graphene Electrodes By Electrophoretic Deposition And Their Synergistic Effects With Pedot And Platinum, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

This research presents a useful electrophoretic deposition (EPD) technique for electrode fabrication from an aqueous colloidal solution of graphene to produce graphene electrodes by the deposition of graphene on to indium-tin oxide (ITO) coated glass. Resultant graphene electrodes are composited with conducting polymer (PEDOT), and platinum nanoparticles, to investigate their synergistic effects. Firstly, PEDOT is composited with graphene by electropolymerization on to the graphene layer. The graphene/PEDOT electrodes demonstrate an improvement in electrochemical response in tetrabutylammonium perchlorate/ acetonitrile solution. Secondly, graphene electrodes are composited with platinum by EPD of platinum nanoparticles on to the graphene layer. The resultant graphene/platinum electrodes …


Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace Jan 2013

Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Wearable electronics offer the combined advantages of both electronics and fabrics. Being an indispensable part of these electronics, lightweight, stretchable and wearable power sources are strongly demanded. Here we describe a daily-used cotton fabric coated with polypyrrole as electrode for stretchable supercapacitors. Polypyrrole was synthesized on the Au coated fabric via an electrochemical polymerization process with p-toluenesulfonic acid (p-TS) as dopant from acetonitrile solution. This material was characterized with FESEM, tensile stress, and studied as a supercapacitor electrode in 1.0 M NaCl. This conductive textile electrode can sustain up to 140% strain without electric failure. It delivers a high specific …


Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond Jan 2013

Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond

Australian Institute for Innovative Materials - Papers

The practical application of two different voltammetric ion selective electrodes (VISE) to measure ion activity in complex solutions has been explored. 7,7,8,8-tetracyanoquinodimethane (TCNQ) and tetrathiafulvalene (TTF) microcrystals adhered to an electrode surface act as a low selectivity voltammetric ion sensor. Resistance drop effects and pH artifacts were minimised by the addition of an "innocent" supporting electrolyte (buffer) to the analyte solution. In this format, addition of an ionophore to improve selectivity resulted in a reduction in current magnitude, due to competition for the ion. In contrast, voltammetry of a thin film containing a redox active species, electrolyte, ionophore and membrane …


Advanced Microwave-Assisted Production Of Hybrid Electrodes For Energy Applications, Peter Sherrell, Jun Chen, Joselito M. Razal, Ivan P. Nevirkovets, Carol Crean, Andrew I. Minett, Gordon G. Wallace Jan 2010

Advanced Microwave-Assisted Production Of Hybrid Electrodes For Energy Applications, Peter Sherrell, Jun Chen, Joselito M. Razal, Ivan P. Nevirkovets, Carol Crean, Andrew I. Minett, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Carbon nanotubes are one of the most prominent materials in research for creating electrodes for portable electronics. When coupled with metallic nanoparticles the performance of carbon nanotube electrodes can be dramatically improved. Microwave reduction is an extremely rapid method for producing carbon nanotube-metallic nanoparticle composites, however this technique has so far been limitied to carbon nanotube soot. An understanding of the microwave process and the interactions of metallic nanoparticles with carbon nanotubes has allowed us to extend this promising functionalisation route to pre-formed CNT elelctrode architectures. Nanoparticle reduction onto pre-formed architectures reduces metallic nanoparticle waste as particles are not formed …