▎ 摘　　要

Manganese dioxide/graphene composite is receiving intensive attention because of its potential applications in energy storage field. In this paper, a novel MnO2 nanocomposite material for high performance supercapacitor was prepared in situ on graphene-like membrane using liquid-polyacrylonitrile as the carbon source. Successful composite formation was confirmed and textural properties were obtained from XRD, FTIR and Raman spectra studies. Morphological characterizations of the nanocomposite were investigated by FE-SEM and TEM measurements. For capacitive properties tests, cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy were carried out in a three-electrode system with a working potential window from 0 to 1 V. The results show that the membrane has a typical graphene-like layer carbon structure. Moreover, the electrochemical performance reveals that the average capacitance of the composite at the mass fraction of graphene-like membrane of 30 % is as high as 302 F g(-1) at 1 A g(-1) in 1 mol L-1 Na2SO4 electrolyte, which permit excellent performance as electrode materials for supercapacitors.