Graphene/ionic liquid binary electrode material for high performance supercapacitor

Herein, we report, the use of hydrogen exfoliated graphene (HEG)/ionic liquid (1-Butyl-3-methylimidazolium terafluoroborate ([BMIM]BF4)) binary electrode material for high performance supercapacitor. HEG/[BMIM] BF4 nanocomposite was prepared and the electrochemical characterization of the electrode has been carried out by cyclic voltammetry and chronopotentiometry. The nanocomposite electrode shows a high specific capacitance (268 F/g at 5mV/s scan rate. Since the ionic liquid has large electrochemical window of 2 V even at atmospheric conditions than the aqueous electrolytes, high energy density of 66.9 Wh/kg at 5 A/g current density could be achieved. © 2011 IEEE.