We report both a facile, scalable method to prepare reduced graphene oxide hydrogels through the electrodeposition of graphene oxide and its use as an electrode for high-performance supercapacitors. Such systems exhibited specific capacitances of 147 and 223 F g(-1) at a current density of 10 A g(-1) when using H2SO4 and H2SO4 + hydroquinone redox electrolytes, respectively.

High density reduced graphite oxide was prepared via a novel precipitation-assisted method, and the micropore area was found to be above 70% of the total surface area for the as-prepared sample. Electrochemical experiments showed that the as-prepared samples exhibited high volumetric capacitance and excellent cycling stability as an electrode material in supercapacitors.

Thick carbon nanofiber (CNF) films were uniformly grown on metal wires with the assistance of pre-deposited NiO nanowalls. The as-prepared wire-shaped composites that integrate the capacitance of CNFs and Ni particles were directly used as electrodes to construct high capacitive fiber supercapacitors for micro-power supplies.

Supercapacitors (or electric double-layer capacitors) are high-power energy storage devices that store charge at the interface between porous carbon electrodes and an electrolyte solution. These devices are already employed in heavy electric vehicles and electronic devices, and can complement batteries in a more sustainable future. Their widespread application could be facilitated by the develo...

© 2013 Uno, licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Singleand Double-Switch Cell Voltage Equalizers for Series-Connected Lithium-Ion Cells and Supe...

Electrochemical energy conversion devices are pervasive in our daily lives. Batteries, fuel cells and supercapacitors belong to the same family of energy conversion devices. They are all based on the fundamentals of electrochemical thermodynamics and kinetics. All three are needed to service the wide energy requirements of various devices and systems. Neither batteries, fuel cells nor electroch...

An efficient and easy method is described which allows modification of supported nanocarbon films with carbon nanotubes (CNTs) from an aqueous colloidal suspension. Subsequently CNTs can be decorated with Pt-nanoparticles directly from an aqueous solution of Pt ions without the need for reducing agents. High performance supercapacitors and electrocatalysts are obtained.

This work reports an efficient strategy to synthesize B,N-codoped porous carbons with a high specific surface area using chitosan as the carbon precursor with the help of boric acid, featuring a high specific capacitance, large operation voltage and excellent cycle stability for supercapacitors.

Nanofibrous hydrogel microspheres are formed by pH gelation of perylene diimide derivatives in emulsion droplets. These microspheres are freeze-dried and subsequently carbonized to produce discrete N-doped nanofibrous carbon microspheres. The carbon microspheres show high performance as electrode materials for supercapacitors.