化学沉积法制备氧化锰/多孔炭复合材料及其电化学性能

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

通过化学沉积法制备了氧化锰/多孔炭(Porous carbon,简称PC)复合材料,考察了氧化锰负载量及热处理温度对其理化性能的影响,探讨了氧化锰/多孔炭复合电极的充放电机理。SEM照片及孔结构测试结果表明,常温下化学沉积法负载氧化锰不但负载均匀,而且还对多孔炭的孔结构起到修饰作用;但经400℃以上高温处理后,其均匀性受到破坏。XRD测试结果表明,经110℃干燥处理及400℃高温处理的复合电极材料负载的氧化锰为无定型结构,800℃时则转变为γ-Mn2O3。经电化学测试表明化学沉积法负载氧化锰可以有效地提高多孔炭电极材料的电能存储容量,当多孔炭负载质量分数1.7%氧化锰,在空气中110℃干燥,制得复合材料的单电极比电容达到340F/g,比单纯的多孔炭电极提高34%。

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℃. Manganese oxides were amorphous when the composite materials were dried at 110 ℃ and 400 ℃, but turned into γ-Mn2O3 at 800 ℃. The single-electrode specific capacitance of composites loaded with mass fraction 1.7 % manganese oxide and dried at 110 ℃ in air reached 340 F/g, which is 34 % higher than that for a pure porous carbon electrode.