Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (08): 2151-2157.doi: 10.3866/PKU.WHXB20100636

• ELECTROCHEMISTRY • Previous Articles     Next Articles

Electrochemical Capacitance of Composites with MnOx Loaded on the Surface of Activated Carbon Electrodes

TIAN Ying1,2, YAN Jing-Wang1, LIU Xiao-Xue1, XUE Rong1, YI Bao-Lian1   

  1. 1. Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, P. R. China;
    2. College of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian 116028, Liaoning Province, P. R. China
  • Received:2009-12-22 Revised:2010-02-25 Published:2010-07-23
  • Contact: YAN Jing-Wang E-mail:yanjw@dicp.ac.cn
  • Supported by:

    The project was supported by the Important Directional Project of ‘the Research and Exploration of Supercapacitor Storage System for Electric Vehicle’ from Dalian Institute of Chemical Physics, Chinese Academy of Sciences.

Abstract:

Activated carbon/manganese oxide (MnOx) composites were prepared by the thermal decomposition of Mn(NO3)2 that was impregnated on the surface of activated carbon XC-72 with a specific surface area of 250 m2·g-1 and on YEC-8 with a specific surface area of 1726 m2·g-1 at 200 ℃. The surface morphology and crystalline structure of the composites were investigated using scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The electrochemical properties of the composites were tested by cyclic voltammetry, galvanostatic charge-discharge, and impedance spectroscopy. We found that α-Mn2O3 and α-Mn3O4 were formed when the composites were annealed at 200 ℃. At mass ratios of C and MnOx of 2∶1 and 9∶1, the specific capacitance of MnOx in the composites of XC-72/MnOx was 499 and 435 F·g-1 and the specific capacitance of MnOx in the composites of YEC-8/MnOx was 554 and 606 F·g-1, respectively. This suggests a significant contribution of pseudocapacitance from MnOx to the specific capacitance of the electrode.

Key words: Supercapacitor, Manganese oxide, Activated carbon, Thermal decomposition

MSC2000: 

  • O646