The invention relates to a method for preparing different-
electrode composite materials of a carbon plate /
manganese dioxide nanometer sheet and the application thereof. In the application, the prepared composite materials serve as the
anode materials, the carbon plate serves as the
cathode materials, and the
anode materials and the
cathode materials are together assembled into an asymmetric
capacitor. The method includes: using a
mesoporous carbon nanometer sheet to serve as a carrier to react with
potassium permanganate (KMnO4) after acidification to obtain the different-
electrode composite materials of the carbon plate /
manganese dioxide nanometer sheet. The acidified carbon plate and the KMnO4 have a
redox reaction, and the carbon plate can increase the
conductivity of the
manganese dioxide nanometer sheet, and simultaneously improve the electrochemical stability and multiplying power characteristics of the composite materials. The content of the manganese dioxide in the composite materials can be controlled by adjusting the time of the
redox reaction, and accordingly the electrochemical performance of the composite materials can be affected. The method is simple, the raw materials are low in cost, the content of the components in the composite materials can be adjusted easily, scale production can be carried out easily, and the assembled asymmetric
capacitor has the advantages of being high in specific
capacitance, high in
energy density and good in stability.