Graphene/MnO₂ composite prepared by a simple method for high performance supercapacitor

Abstract

MnO2 nanoparticles are anchored on the graphene nanosheets and make a graphene nanosheets/MnO2 (GMn) composite by thermal decomposition for application in supercapacitor. The GMn composite exhibits specific capacitance of 450 F g− 1 at 1 A g− 1, which is more than three times higher than that of as-prepared graphene sheets. Meanwhile, the composite shows excellent cycle stability without decline over 5000 cycles. The high electrochemical performance of the GMn electrodes is attributed to the prevention of graphene aggregation by the MnO2 nanoparticles, and the synergistic effects between graphene and MnO2 nanoparticles.