Electrochemical Characterization of Porous Graphene Film for Supercapacitor Electrode

Abstract

The authors fabricate the porous graphene films through embossing process and vacuum filtration method and demonstrate their superior electrochem. properties as supercapacitor electrode materials. Insertion/removal of polystyrene nanoparticles between the graphene sheets allows to provide pore structures, leading to the effective prevention of restacking in graphene films. As-prepd. porous graphene films have a large surface area, a bicontinuous porous structures, high elec. cond., and excellent mech. integrity. The electrochem. properties of the porous graphene films as electrode materials of supercapacitor were studied by using aq. H2SO4 and ionic liq. soln. under three-electrode system. The porous graphene films exhibit a high specific capacitance (284.5 F/g), which is 2-fold higher than that of packing graphene films (138.9 F/g). The rate capability (98.7% retention) and long-term cycling stability (97.2%) for the porous graphene films are significantly enhanced, due to the facilitated ion mobility between the graphene layers. [on SciFinder(R)]