Fabrication of mesoporous cobalt oxide (Co3O4) film by electrochemical method for electrochemical capacitor.

Mesoporous cobalt oxide (Co3O4) films were deposited on ITO coated glass substrates by electrodeposition from an aqueous CoSO4 solution using CTAB (cetyltrimethylammonium bromide) as the templating agent. The structures of the synthesized films were characterized by X-ray diffraction, and X-ray photoelectron spectroscopy. The presence of mesoporosity was confirmed by transmission electron microscopy and small angle X-ray diffraction analyses. The mesoporous structures of the synthesized films were found to be strongly dependent on the deposition conditions, such as deposition voltage, deposition time, temperature and concentration of templating agent. Cyclic voltammetry and discharging curves were used to examine the electrochemical properties as a capacitor. The mesoporous films prepared with CTAB templating showed a much higher specific capacitance and current density than the nonporous electrode prepared without CTAB templating.