多孔炭电极的结构特性与其电化学性能

Structural characteristic and electrochemical performance of porous carbonaceous electrodes

以中间相炭微球作为前驱体,在不同条件下进行炭化预处理,再经过化学活化热处理制备活性中间相炭微球,以此为电极材料组装超级电容器并进行电化学测试。研究发现:中间相炭微球的碳层取向随着炭化温度的升高而趋于规整,碳质前驱体整体抵御活化剂刻蚀的能力加强,表现为活化收率随炭化预处理温度的升高而增加,而比表面积和孔容则呈下降趋势;经过炭化预处理的活性炭微球系列样品具有良好电容保持率,在50mA/cm2放电时电容下降仅为1mA/cm2条件下的30%;将活性炭微球的碘吸附值与双电层比电容进行线性拟合,发现碘值与比电容具有良好的线性相关性。

Activated carbons were prepared from mesocarbon microbeads （MCMBs） by means of different carbonization conditions and chemical activations. Electrochemical examinations were executed with supercapacitors by using these activated carbons as electrode materials. The relationship between structure characteristics of carbonaceous precursor and carbonization treatment was discussed. The results show that activation yield increases with the increasing carbonization temperature, specific surface area and pore volume go with the opposite direction. As for the electrochemical performance, the series of porous carbons have good capacitance stability at higher discharging current. Specific capacitance at 50 mA/cm^2 is over 70% of the figure for 1 mA/cm^2. In addition, there exists a significant linear relationship between iodine adsorption value of activated carbon and specific capacitance.