Mesoporous manganese oxide electrodeposited using a mixture of surfactants for supercapacitor electrodes

초록

In recent years, transition metal oxide is one of the most prospective active materials as an electrode material for both double layer capacitance and pseudo capacitance. Among the various transition metal oxides, material based on manganese oxide is the most promising candidate for supercapacitor owing to their low cost, high abundance, large theoretical specific capacitance and environmentally-friendly properties. In addition, mesoporous materials have a large specific surface area and pore volume, leading to improved electrochemical performance. In this work, mesoporous manganese oxide was electrochemically fabricated with a mixture of surfactants on the indium-tin-oxide (ITO)-coated glass from an aqueous solution with 10 mM Mn(Ac)2. Proper amount of mixed surfactants was added to the solution for synthesis of mesoporous films. The electrodeposition was carried out under constant potential at room temperature. The crystallinity and phase of the prepared manganese oxide were investigated by X-ray diffraction (XRD) and the mesoporous structure of the synthesized electrodes were measured by small angle X-ray diffraction (SAXRD). The morphology and the surface properties of the samples were also characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical properties were determined by Tafel slope and cyclic voltammetry (CV) in a standard three electrode system using a potentiostat.