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Articles 1 - 16 of 16
Full-Text Articles in Physical Sciences and Mathematics
Pegylation Of Platinum Bio-Electrodes, Zhilian Yue, Paul J. Molino, Xiao Liu, Gordon G. Wallace
Pegylation Of Platinum Bio-Electrodes, Zhilian Yue, Paul J. Molino, Xiao Liu, Gordon G. Wallace
Gordon Wallace
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
Conducting Polymer Coated Neural Recording Electrodes, Alexander R. Harris, Simon Morgan, Jun Chen, Robert M. Kapsa, Gordon G. Wallace, Antonio Paolini
Gordon Wallace
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 …
Direct Eit Reconstructions Of Complex Admittivities On A Chest-Shaped Domain In 2-D, Sarah J. Hamilton, Jennifer L. Mueller
Direct Eit Reconstructions Of Complex Admittivities On A Chest-Shaped Domain In 2-D, Sarah J. Hamilton, Jennifer L. Mueller
Mathematics, Statistics and Computer Science Faculty Research and Publications
Electrical impedance tomography (EIT) is a medical imaging technique in which current is applied on electrodes on the surface of the body, the resulting voltage is measured, and an inverse problem is solved to recover the conductivity and/or permittivity in the interior. Images are then formed from the reconstructed conductivity and permittivity distributions. In the 2-D geometry, EIT is clinically useful for chest imaging. In this work, an implementation of a D-bar method for complex admittivities on a general 2-D domain is presented. In particular, reconstructions are computed on a chest-shaped domain for several realistic phantoms including a simulated pneumothorax, …
Nanostructured Carbon Electrodes, Gordon G. Wallace, Jun Chen, Dan Li, Simon E. Moulton, Joselito M. Razal
Nanostructured Carbon Electrodes, Gordon G. Wallace, Jun Chen, Dan Li, Simon E. Moulton, Joselito M. Razal
Gordon Wallace
In its conducting form, carbon has proven to be a versatile, robust and high performing electrode material in areas such as energy conversion, energy storage and even medical bionics. In our laboratories we have been interested in the fabrication and utilization of nanostructured electrodes based on more recently discovered forms of carbon. These include carbon nanotubes and graphene.
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
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
Gordon Wallace
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 …
Flexible And Compressible Goretex-Pedot Membrane Electrodes For Solid-State Dye-Sensitized Solar Cells, Attila J. Mozer, Dillip K. Panda, Sanjeev Gambhir, Anthony C. Romeo, Bjorn Winther-Jensen, Gordon G. Wallace
Flexible And Compressible Goretex-Pedot Membrane Electrodes For Solid-State Dye-Sensitized Solar Cells, Attila J. Mozer, Dillip K. Panda, Sanjeev Gambhir, Anthony C. Romeo, Bjorn Winther-Jensen, Gordon G. Wallace
Gordon Wallace
A porous, flexible electrode based on a PTFE (Teflon) membrane (Goretex) coated with a metallic current collector and a conducting polymer (poly(3,4-ethylenedioxythiophene), PEDOT) has been developed for applications in solidstate dye-sensitized solar cells. Its low sheet resistance and compressibility make it an ideal electrode on uneven TiO2 surfaces with high efficiency and reproducibility. The porous nature of the electrode enables the feed-through of reactants and treatment agents, which opens up exciting opportunities to interface these photoelectrochemical devices with electrocatalytic, energy conversion, and storage systems. Postfabrication bonding of the photoanode and the Goretex-Au-PEDOT electrode is demonstrated.
Enhanced Performance Of Dye Sensitized Solar Cells Utilizing Platinum Electrodeposit Counter Electrodes, Attila J. Mozer, George Tsekouras, Gordon G. Wallace
Enhanced Performance Of Dye Sensitized Solar Cells Utilizing Platinum Electrodeposit Counter Electrodes, Attila J. Mozer, George Tsekouras, Gordon G. Wallace
Gordon Wallace
Enhanced performance was observed for dye-sensitized solar cells (DSSCs) utilizing counter electrodes based on Pt electrodeposits compared to counter electrodes based on sputtered Pt. Scanning electron microscopy of Pt electrodeposits revealed that the use of an initial cathodic overpotential pulse followed by steady electrodeposition at a mild cathodic potential yielded ∼40nm particles, compared to ∼600nm particles when no such pulse was used. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) of electrode materials suggested that Pt electrodeposits would give enhanced performance as DSSC counter electrodes compared to sputtered Pt, and this was confirmed by device testing. EIS characterization of DSSCs under …
Pegylation Of Platinum Bio-Electrodes, Zhilian Yue, Paul J. Molino, Xiao Liu, Gordon G. Wallace
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.
Intrinsically Stretchable Supercapacitors Composed Of Polypyrrole Electrodes And Highly Stretchable Gel Electrolyte, Chen Zhao, Caiyun Wang, Zhilian Yue, Kewei Shu, Gordon G. Wallace
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 …
Transparent Actuator Made With Few Layer Graphene Electrode And Dielectric Elastomer, For Variable Focus Lens, Taeseon Hwang, Hyeok-Yong Kwon, Joon-Suk Oh, Jung-Pyo Hong, Seung-Chul Hong, Youngkwan Lee, Hyouk Ryeo Choi, Kwang J. Kim, Mainul Hossain Bhuiya, Jae Do Nam
Transparent Actuator Made With Few Layer Graphene Electrode And Dielectric Elastomer, For Variable Focus Lens, Taeseon Hwang, Hyeok-Yong Kwon, Joon-Suk Oh, Jung-Pyo Hong, Seung-Chul Hong, Youngkwan Lee, Hyouk Ryeo Choi, Kwang J. Kim, Mainul Hossain Bhuiya, Jae Do Nam
Mechanical Engineering Faculty Research
A transparent dielectric elastomer actuator driven by few-layer-graphene (FLG) electrode was experimentally investigated. The electrodes were made of graphene, which was dispersed inN-methyl-pyrrolidone. The transparent actuator was fabricated from developed FLG electrodes.The FLG electrode with its sheet resistance of 0.45 kΩ/sq (80 nm thick) was implemented to mask silicone elastomer. The developed FLG-driven actuator exhibited an optical transparency of over 57% at a wavenumber of 600 nm and produced bending displacement performance ranging from 29 to 946 μm as functions of frequency and voltage. The focus variation was clearly demonstrated under actuation to study its application-feasibility in …
The Detailed Characterization Of Electrochemically Switchable Molecular Assemblies On Silicon Electrodes, Simone Ciampi, Michael James, Moinul H. Choudhury, Nadim A. Darwish, J Justin Gooding
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 …
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
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 …
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
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 …
Conducting Polymer Coated Neural Recording Electrodes, Alexander R. Harris, Simon Morgan, Jun Chen, Robert M. Kapsa, Gordon G. Wallace, Antonio Paolini
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 …
Applications Of Voltammetric Ion Selective Electrodes To Complex Matrices, Alexander R. Harris, Jie Zhang, Robert W. Cattrall, Alan M. Bond
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 …
Electrochemically Synthesized Stretchable Polypyrrole/Fabric Electrodes For Supercapacitor, Binbin Yue, Caiyun Wang, Xin Ding, Gordon G. Wallace
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 …