Scalable fabrication of high quality graphene by exfoliation of edge sulfonated graphite for supercapacitor application

Abstract

Graphene sheets with high quality and dispersibility were prepared by exfoliation of edge sulfonated graphite. Tosyl-graphene (TsG) dispersion in N-methyl-pyrrolidone (NMP) readily reached up to 16 mg mL⁻¹ without any surfactants. TsG enjoys intact crystal planes and flexible framework. When employed as electrode material for supercapacitor, TsG shows outstanding specific capacitance of 180 F g⁻¹ at a current density of 0.5 A g⁻¹, and excellent cycling stability (only 2% loss after 10 000 cycles), which can offer enormously potential for super-capacitors and other highly desired energy storage devices.