Supercapacitor performances of MnO2 and MnO2/ reduced graphene oxide prepared with various electrodeposition time

MnO2 and MnO2/Reduced graphene oxide composite electrodes with different electrodeposition time after alcohol infiltration were prepared by a simple electrochemical deposition method without any binder under argon atmosphere. Scanning electron microscope, transmission electron microscope, X-ray photoelectron spectroscopy and other analytical methods were used to analyze the morphology, microstructure and other properties of the composite material. Galvanostatic charge-discharge, Cyclic Voltammetry, Chronoamperometry and Electrochemical impedance spectroscopy were used to assess the electrochemical performance of the prepared electrodes. MnO2/RGO composite electrode deposited in a short time (50 s) has excellent electrochemical performance, the specific capacitance can maintain 175 F g−1 at a high current density of 20 A g−1, and the energy density can reach 41.27 Wh Kg−1 (1 A g−1). In addition, it has lower charge transfer resistance in 1 M Na2SO4 solution (0.22 Ω).