Nanoporous metal based flexible asymmetric pseudocapacitors

Abstract

We report a flexible asymmetric supercapacitor assembled by polypyrrole (PPy) and manganese oxide supported by ultrathin three-dimensional nanoporous gold (NPG) electrodes. The highly conductive and free-standing NPG films act as both supports of the active materials and current collectors of the supercapacitor, which evidently enhance the specific capacitance of active materials of both the conducting polymer and the metal oxide. The high energy density and high power density can be realized from the PPy–NPG//MnO₂–NPG asymmetric supercapacitor because of the wide cell voltage in an aqueous electrolyte and high specific capacitances of both PPy and MnO₂ enhanced by NPG.