MnO2/ZnO porous film: Electrochemical synthesis and enhanced supercapacitor performances

MnO2/ZnO porous compound film was synthesized by a two-step electrochemical route at room temperature. The structure and surface morphology of the as-preparedMnO(2)/ZnO filmwere characterized by X-ray diffraction and scanning electron microscopy. The supercapacitive behavior of the as-prepared MnO2/ZnO film in aqueous 0.1 M Na2SO4 electrolyte was studied by cyclic voltammetry, charge/discharge cycling and electrochemical impedance spectroscopy. In addition, single MnO2 film was also synthesized and characterized by the same method for comparison. The SEM results show that the as-prepared MnO2/ZnO film exhibits a uniform porous net structure while the single MnO2 film shows a bulk structure with uneven surface morphology. The electrochemical results indicate that the MnO2/ZnO porous film shows good capacitive behavior with a specific capacitance of 570.9 mu F cm(-2) which is three times larger than that of the single MnO2 film (179.4 mu F cm(-2)), which reveals a potential application prospect in electrochemical supercapacitors. (C) 2015 Elsevier B.V. All rights reserved.