Fabrication of Porous Carbon Spheres/Manganese Oxide Composite Electrodes for Electrochemical Capacitors

摘要

Manganese oxide (MnCh) has been successfully deposited on the surface of porous carbon spheres (CS) by in-situ co-precipitation. The electrochemical capacitive behaviors of the resulting ternary composites (MnO_2/CS) as active electrode materials have been investigated in 0.1 M Na_2SO_4 by different electrochemical techniques including cyclic voltammetry, galvanostatic charge-discharge, and impedance spectroscopy. The results show that the specific capacitance of MnO_2/CS composites is 488.8 F g~(-1)' and the maximum power density is 12.5 kW kg~(-1). The composites also display a good electrochemical stability, and the discharge capacitance retains about 87% of the initial value after 1000 consecutive cycling.