Abstract
A three-dimensional composite electrode of graphene aerogel and nickel foam was initially prepared by one-pot hydrothermal process. The electrochemical performances of such prepared electrode was investigated with cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy, and the results showed a specific capacitance of 217 F/g at 1.0 A/g, 88% specific capacitance kept as the current density is increased from 1 to 10 A/g, and 91.4% of the original capacitance maintained after cycling 5000 times in 6 mol/L KOH electrolyte at 10 A/g. These improved electrochemical performances were ascribed to the template effect of nickel foam and the chemical reduction of ethylenediamine.