Asymmetric supercapacitor based on nanostructured porous manganese oxide and reduced graphene oxide in aqueous neutral electrolyte

Abstract

A High energy, asymmetric supercapacitor (ASC) has been constructed using porous manganese oxide (MnO2) nanostructures as positive electrode and reduced graphene oxide (RGO) as negative electrode in 1M Na2SO4 electrolyte. The ASC device exhibits excellent electrochemical performance, when the device is assembled with optimal mass ratio. The energy density is 22.2Whkg−1 at a power density of 101Wkg−1, when the device is cycled reversibly in the high potential range of 0–2V. The asymmetric supercapacitor device also exhibits a superior cycling stability with 90% retention of the initial specific capacitance after 3000 cycles.