| Supercapacitors is a new energy storage component. With its large capacity, fast charge-discharge capability and a longer cycle life, etc; they have multiple applications including automobiles, portable devices, aeronautics and astronautics, military, etc. Electrode materials play an important role in supercapacitors. In this paper, we conducted chemical liquid phase deposition method in preparing powder, and electrode materials are studied by modification. The structure and ameliorated morphology of MnO2 is analyzed by X-rays diffraction (XRD) and scanning electron microscopy (SEM). The electrochemistry performance is tested by cyclic voltammetric measurements (CV), AC impedance and constant charge/discharge measurements.First of all, MnO2 powders were fabricated in five ways by liquid phase deposition method. Comprehensive analysis showed that the powder prepared by the method of potassium permanganate and sodium bisulfite reaction had the best electrochemical performance. Detected by XRD and SEM analysis, amorphous of MnO2 particle size of 20～50nm. According the MnO2:graphite:PTFE ratio was 65:30:5(wt%) made electrode, in the 1mol/L of (NH4)SO4 solution, the current density of 5 mA·cm-2, the specific capacitance of single electrode reached 305.25F/g.Then, nano-composites MnO2 material made by the method of potassium permanganate and sodium bisulfite reaction adding different proportion of treated CNT, it can improved the MnO2 sample agglomeration and its electrochemistry performance. When the rate of the doping was 10%, electrochemical measurement revealed that the specific capacitance of single electrode reached the maximum, improved to be 347.32 F/g.Finally, some other elements (antimony trioxide and zirconium dioxide) were doped into the MnO2 powder. We found that the discharge capacity reached 375.75F/g when n(Mn):n(Sb) was 100:10. However, doping in the zirconium couldn't improve MnO2 sample's electrochemistry performance.
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