Manganese oxide/porous carbon composites produced by chemical deposition and their electrochemical performance

Manganese oxide/porous carbon composites were prepared by chemical deposition. The effects of the amount of manganese oxide loading and heat treatment temperature on the physical and electrochemical properties of the composites were investigated by SEM, XRD and charge/discharge testing. It was found that manganese oxide was uniformly loaded into porous carbon at low temperatures and pore structures were also modified by the reaction of carbon atoms with the manganese oxide. However the loading uniformity of manganese oxide was destroyed when the heat treatment temperature was above 400 degrees C. Manganese oxides were amorphous when the composite materials were dried at 110 degrees C and 400 degrees C, but turned into gamma-Mn2O3 at 800 degrees C. The single-electrode specific capacitance of composites loaded with mass fraction 1.7 % manganese oxide and dried at 110 degrees C in air reached 340 F/g, which is 34 % higher than that for a pure porous carbon electrode.