MnO2/graphene composite electrodes for supercapacitors: the effect of graphene intercalation on capacitance

Abstract

MnO₂/graphene composites were prepared for the electrode material of supercapacitors. MnO₂ was synthesized on a gold plate by the electrodeposition method. Graphene prepared by thermal CVD was transferred onto the MnO₂ layer. These processes were repeated to make multilayer structures. The optimal performance of the MnO₂/graphene composite was examined as a function of the number of graphene layers in MnO₂. The morphology of MnO₂ on graphene was confirmed by SEM and TEM, and the capacitance of the electrode was investigated by cyclic voltammetry and galvanostatic charge/discharge test. The graphene layer provides the electro-conductivity of MnO₂, and then leads to enhancement of the capacitance of MnO₂.