Manganese oxide/carbon composite electrodes for electrochemical capacitors

Multi-layer and co-deposition composite electrodes were prepared by introducing the carbon powders into the anodically deposited hydrous manganese oxide. The surface morphology and crystal structure of the electrodes were examined by scanning electron microscope and glancing angle X-ray diffraction. Cyclic voltammetrty and chronopotentiometry were also performed to evaluate the electrochemical characteristics of the electrodes prepared. These composite electrodes with rough surface, consisted of amorphous hydrous manganese oxide and carbon powder, were confirmed to possess the ideal capacitive property. The specific capacitance, high power capability and cyclic stability of the hydrous manganese oxide/carbon composite electrodes were superior to that of the plain hydrous manganese oxide electrode. (C) 2004 Elsevier B.V. All rights reserved.