以中间相沥青(Mesophase pitch,MP)为前驱体、KOH作为活化剂,分别采用直接活化法、预炭化活化法制备出活性炭(Activated carbons,ACs).采用N2吸附法对所制ACs的比表面积、孔径分布进行分析.将所制ACs应用于电化学电容器电极材料,进行恒流充放电、循环伏安电化学分析.结果表明:电极的电化学性能不仅受活性炭比表面积、孔结构的影响,也与活性炭的微观形貌有关.其中预炭化活化法ACs颗粒具有片层结构,更有利于炭电极与电解液的浸润,提高微孔比表面积对比电容的贡献.%Activated carbons ( ACs) prepared from mesophase pitch and carbonized mesophase pitch by KOH activation were used to fabricate electrodes for electric double layer capacitors. Nitrogen adsorption at 77 K was used to characterize the specific surface area and pore structure of the ACs, which showed a bimodal pore size distribution. The performance of the ACs in an organic electrolyte ( 1 mol/L of Et4NBF4 in propylene carbonate) was investigated with voltage sweep cyclic voltammetry and constant current charge-discharge cycling. Results show that the capacitance of the ACs not only depends on the surface area and pore size distribution , but also on carbonization treatment. SEM images show that the AC particles from carbonized pitch are formed by stacking of layered slices, which favors an infiltration of solvent into the inner surface of the carbon and improves the capacitance per unit area of micropores.
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