Acta Phys. -Chim. Sin. ›› 2009, Vol. 25 ›› Issue (10): 1991-1997.doi: 10.3866/PKU.WHXB20091025

• ARTICLE • Previous Articles     Next Articles

Study on Meso-C/MnO2 Asymmetric Supercapacitors

SUN Zhe, LIU Kai-Yu, ZHANG Hai-Feng, LI Ao-Sheng, XU Xiao-Cun   

  1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China|Changsha Longtech Co. Ltd., Changsha 410083, P. R. China
  • Received:2009-05-13 Revised:2009-06-29 Published:2009-09-29
  • Contact: LIU Kai-Yu E-mail:kaiyuliu@263.net

Abstract:

Mesoporous MnO2 and mesoporous carbon were prepared using silica mesoporous molecular sieves (SBA-15) as a hard template. A meso-C/MnO2 asymmetrical supercapacitor was assembled and characterized in 6 mol·L-1 KOHelectrolyte. Low X-ray diffraction (LXRD), transmission electron microscopy (TEM), and nitrogen adsorption-desorption results indicated that the as-prepared samples had mesoporous structures, large specific surface areas, and a narrow pore diameter distribution range. Galvanostatic charge/discharge, cyclic voltammetry, and AC (alternating current) impedance were used to investigate the electrochemical performance. At 0.1 A·g-1 current density, different potentials were applied to obtain the optimum cell voltage of 1.8 V. Under this condition, the supercapacitor exhibited good charge/discharge capacities. Results showed that the equivalent series resistance (ESR), power density, and energy density were 1.15 Ω, 89.0 W·kg-1, and 31.3 Wh·kg-1, respectively. The initial specific capacitance was 76.7 F·g-1 and 69.5 F·g-1 was obtained after 1000 cycles.

Key words: Asymmetric supercapacitor, Mesoporous MnO2, Mesoporous carbon, Electrochemical performance

MSC2000: 

  • O646