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Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

Colloidal Ionic Supercapacitors, Kun-Feng Chen, Dong-Feng Xue Dec 2015

Colloidal Ionic Supercapacitors, Kun-Feng Chen, Dong-Feng Xue

Journal of Electrochemistry

Supercapacitors have high power density and long cycle life compared with battery systems, but they still suffer from low energy density at the same time. In order to increase the energy density of supercapacitors, we have developed a new type of pseudocapacitor, called colloidal ion supercapacitor, which can directly use commercial metal salts as electrode materials and form electroactive matter by in-situ electrochemical reactions without the need of additional materials synthesis processes. Colloidal ion supercapacitor can fully utilize the redox reaction of metal cations with multiple oxidation states, which can completely release the stored electrical energy of multiple-valence cations, leading …


Carbon Aerogel/Nickel Foam As Electrode For High-Performance Supercapacitor, Zhong Wu, Xin-Bo Zhang Dec 2015

Carbon Aerogel/Nickel Foam As Electrode For High-Performance Supercapacitor, Zhong Wu, Xin-Bo Zhang

Journal of Electrochemistry

Herein, a facile synthesis has been explored to prepare carbon aerogel/Ni foam. Graphene oxide, resorcinol and formaldehyde serve as precursors and polymerize in-situ on the Ni foam after hydrothermal synthesis at 85 oC. After lyophilization treatment, the carbon aerogel/Ni foam with porous structure can be obtained. Electrochemical investigations reveal that the carbon aerogel/Ni foam exhibits superior performances in both aqueous and organic electrolytes involving high specific capacitance and long-term cycling stability. The excellent properties can be ascribed to the unique formation and porous structure, which allows more effective transportations of electron and electrolyte ion.


Progress Of Self-Supported Supercapacitor Electrode Materials Based On Carbon Substrates, Shui-Jian He, Wei Chen Dec 2015

Progress Of Self-Supported Supercapacitor Electrode Materials Based On Carbon Substrates, Shui-Jian He, Wei Chen

Journal of Electrochemistry

Self-supported electrode materials have been widely used in supercapacitors. Carbon materials are promising substrates in building self-supported electrode materials attributed to their diverse structures, rich resource, relatively low cost and high stability. Combined with our own research in this field, we summarize here the recent progress on the synthesis of self-supported electrode materials and their supercapacitance properties. The overall synthetic strategy could be divided into two categories: “top-down” and “bottom-up”. We hope this review is helpful for the development and application of renewable sources in self-supported electrode materials.


An Organic Mixed Ion-Electron Conductor For Power Electronics, Abdellah Malti, Jesper Edberg, Hjalmar Granberg, Zia Ullah Khan, Jens W. Andreasen, Xianjie Liu, Dan Zhao, Hao Zhang, Yulong Yao, Joseph W. Brill, Isak Engquist, Mats Fahlman, Lars Wågberg, Xavier Crispin, Magnus Berggren Dec 2015

An Organic Mixed Ion-Electron Conductor For Power Electronics, Abdellah Malti, Jesper Edberg, Hjalmar Granberg, Zia Ullah Khan, Jens W. Andreasen, Xianjie Liu, Dan Zhao, Hao Zhang, Yulong Yao, Joseph W. Brill, Isak Engquist, Mats Fahlman, Lars Wågberg, Xavier Crispin, Magnus Berggren

Physics and Astronomy Faculty Publications

A mixed ionic–electronic conductor based on nanofibrillated cellulose composited with poly(3,4-ethylene-dioxythio­phene):­poly(styrene-sulfonate) along with high boiling point solvents is demonstrated in bulky electrochemical devices. The high electronic and ionic conductivities of the resulting nanopaper are exploited in devices which exhibit record values for the charge storage capacitance (1F) in supercapacitors and transconductance (1S) in electrochemical transistors.


An Investigation On Electrochemical Performance Of Supercapacitor Electrode Materials Prepared By Mno2 With Four Different Crystal Forms, Zhen-Kun Wei, Xiao-Zhen Hua, Ke Xiao, Xian-Liang Zhou, Zhi-Guo Ye Aug 2015

An Investigation On Electrochemical Performance Of Supercapacitor Electrode Materials Prepared By Mno2 With Four Different Crystal Forms, Zhen-Kun Wei, Xiao-Zhen Hua, Ke Xiao, Xian-Liang Zhou, Zhi-Guo Ye

Journal of Electrochemistry

Four types of α-MnO2, β-MnO2, γ-MnO2 and δ-MnO2 powders were synthesized by relatively simple methods. The differences in crystal structures and surface morphologies for these forms of MnO2 were investigated by using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA) and specific surface area analysis (BET). The electrochemical performances were characterized by cyclic voltammetry (CV) and stability analysis. Based on the experimental results, four kinds of MnO2 electrodes showed good capacity properties, and the α-MnO2 electrode had the largest specific capacity due to the highest specific surface …


Carbide-Derived Carbon By Electrochemical Etching Of Vanadium Carbides, Luis G.B. Camargo, Benjamin G. Palazzo, Greg Taylor, Zach A. Norris, Yash K. Patel, Jeffrey D. Hettinger, Lei Yu Aug 2015

Carbide-Derived Carbon By Electrochemical Etching Of Vanadium Carbides, Luis G.B. Camargo, Benjamin G. Palazzo, Greg Taylor, Zach A. Norris, Yash K. Patel, Jeffrey D. Hettinger, Lei Yu

Faculty Scholarship for the College of Science & Mathematics

Carbide-derived Carbon (CDC) has been demonstrated to be an excellent electrode material for electrochemical devices including supercapacitors due to its chemical and electrochemical stability, large specific surface area and controllable pore size and morphology. Currently, CDC is prepared from metal carbides by chlorination in a chlorine gas atmosphere at temperatures of 350°C or higher. In this paper, conversion using electrochemical methods is reported, which can be achieved by oxidizing vanadium carbides (VC or V2C) in aqueous solutions at room temperature and a mild electrode potential to prepare CDC thin film as electrode materials for “on-chip” supercapacitiors. It was …


A Facile Approach For Fabrication Of Mechanically Strong Graphene/Polypyrrole Films With Large Areal Capacitance For Supercapacitor Applications, Yu Ge, Caiyun Wang, Kewei Shu, Chen Zhao, Xiaoteng Jia, Sanjeev Gambhir, Gordon G. Wallace Jan 2015

A Facile Approach For Fabrication Of Mechanically Strong Graphene/Polypyrrole Films With Large Areal Capacitance For Supercapacitor Applications, Yu Ge, Caiyun Wang, Kewei Shu, Chen Zhao, Xiaoteng Jia, Sanjeev Gambhir, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Substantial progress has been made in free-standing flexible graphene-based films for flexible supercapacitors. However, there are limited reports on the areal capacitance of these electrodes, which is an important parameter for practical applications, especially in miniaturized electronic devices. Herein we report the facile fabrication of robust flexible graphene/polypyrrole nanoparticle films. PPy NPs act as the "spacer" between graphene layers creating hierarchical structures. This free-standing film shows excellent mechanical properties with a fracture strength of 16.89 MPa and Young's modulus of 11.77 MPa. The resulting film electrode delivers a large areal specific capacitance of 216 mF cm−2, which is higher or …


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, …


High-Performance Flexible All-Solid-State Supercapacitor From Large Free-Standing Graphene-Pedot/Pss Films, Yuqing Liu, Bo Weng, Joselito M. Razal, Qun Xu, Chen Zhao, Yuyang Hou, Shayan Seyedin, Rouhollah Jalili, Gordon G. Wallace, Jun Chen Jan 2015

High-Performance Flexible All-Solid-State Supercapacitor From Large Free-Standing Graphene-Pedot/Pss Films, Yuqing Liu, Bo Weng, Joselito M. Razal, Qun Xu, Chen Zhao, Yuyang Hou, Shayan Seyedin, Rouhollah Jalili, Gordon G. Wallace, Jun Chen

Australian Institute for Innovative Materials - Papers

Although great attention has been paid to wearable electronic devices in recent years, flexible lightweight batteries or supercapacitors with high performance are still not readily available due to the limitations of the flexible electrode inventory. In this work, highly flexible, bendable and conductive rGO-PEDOT/PSS films were prepared using a simple bar-coating method. The assembled device using rGO-PEDOT/PSS electrode could be bent and rolled up without any decrease in electrochemical performance. A relatively high areal capacitance of 448 mF cm-2 was achieved at a scan rate of 10 mV s-1 using the composite electrode with a high mass loading (8.49 mg …


Supercapacitor Energy Storage Based-Upqc To Enhance Ride-Through Capability Of Wind Turbine Generators, Gangatharan Sivasankar, Velu Suresh Kumar Jan 2015

Supercapacitor Energy Storage Based-Upqc To Enhance Ride-Through Capability Of Wind Turbine Generators, Gangatharan Sivasankar, Velu Suresh Kumar

Turkish Journal of Electrical Engineering and Computer Sciences

The recent advancement in electric energy storage technologies provides an opportunity of using energy storage systems to address the issues of grid-integrated wind energy conversion systems. This paper proposes a novel configuration of a unified power quality conditioner (UPQC) with a supercapacitor-based short-term energy storage system for managing wind power intermittency during grid faults. The STATCOM-like compensation device can compensate only current related issues. The dynamic voltage restorer can compensate voltage-related issues but it can contribute only 50{\%} voltage due to converter rating limitations. Moreover, real power handling capabilities of these devices are very poor. This new UPQC scheme can …