Mesoporous carbon decorated graphene as an efficient electrode material for supercapacitors

Abstract

A novel mesoporous carbon decorated graphene (MCG) material was fabricated as an effective electrode material for supercapacitors through the rational design of the nanostructure. The mesoporous carbon layer served as an effective inhibitor of the aggregation of the graphene sheets and a place of charge accumulation, while the graphene sheets acted as a highly conductive carbon frame. Compared to the pure graphene, the as-obtained MCG electrode materials exhibited higher surface area and more favorable pore size distribution. The electrochemical measurements of CV, galvanostatic charge–discharge and the impedance spectrum were used to investigate the electrochemical performance of the as-fabricated MCG electrodes. In particular, the results showed that the MCG-20 electrode could deliver a specific capacitance as high as 213.3 F g⁻¹ at a current density of 0.5 A g⁻¹. The other electrochemical observations revealed that the as-fabricated electrodes offered reduced ESR and excellent cycling stability. Such results demonstrate that this graphene based composite material is a promising candidate for the electrode material for high-performance supercapacitors.