Microwave-assisted synthesis of functionalized graphene on Ni foam as electrodes for supercapacitor application

The electrodes of supercapacitors were prepared via a simple and convenient strategy by microwave-assisted synthesis of functionalized graphene on Ni foam (FG-Ni foam) in ambient condition. The functionalized graphene on Ni foam was directly used as electrode for electrochemical double layer capacitance without any conductive agents and polymer binders, such as acetylene black and polyterafluoroethylene. The direct contact between FG and the foam current collector without any polymer binder helps to decrease the resistance of the FG-Ni foam electrode and improve the cycle life of the supercapacitor based on the FG-Ni foam electrodes. FG-Ni foam exhibits good electrochemical performance with a maximum specific capacitance of 265 Fg(-1) at the charge/discharge current density of 1 A g(-1) with 5 M NaOH as electrolyte. After 10,000 cycling GCD tests, a high level retaining specific capacitance of 261 F g(-1) was obtained which still retained 97.7% of the initial capacity and the charge/discharge efficiency was approximate to 99.9%. (C) 2013 Elsevier Ltd. All rights reserved.