超级电容器用活性炭电极表面氧化改性后的电化学性能Electrochemical performance of surface oxidized activated carbon electrodes for supercapacitor
杜嬛;王成扬;郭春雨;时志强;
摘要(Abstract):
以椰壳活性炭和杏壳活性炭为原料,采用浓硝酸液相氧化改性处理后,制成以 KOH 为电解液的超级电容器的炭电极。采用低温 N_2吸附法表征了活性炭的孔结构性质,并采用循环伏安法和交流阻抗法考察了活性炭电极的电化学性能。实验表明,经浓硝酸氧化处理后,活性炭的比表面积和孔容降低,平均孔径增大。但由于氧化处理后材料赝电容的增加,椰壳活性炭和杏壳活性炭的放电容量不但没有降低.反由原来的114 F·g~(-1)和98 F·g~(-1)分别增大到166 F·g~(-1)和157 F·g~(-1)。同时,浓硝酸氧化降低了活性炭电极的表面电荷迁移电阻和时间常数。
关键词(KeyWords): 活性炭;超级电容器;表面氧化改性;赝电容;表面电荷迁移电阻;时间常数
基金项目(Foundation):
作者(Author): 杜嬛;王成扬;郭春雨;时志强;
Email:
DOI: 10.14024/j.cnki.1004-244x.2008.02.023
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