一种新型氧化还原电解液电化学电容器体系  

A New Kind of Redox Electrolyte Electrochemical Capacitor System

作　　者：李强[1,2] 李开喜[1] 孙国华[1,2] 范慧[1] 谷建宇[1] 

机构地区：[1]中国科学院山西煤炭化学研究所,炭材料重点实验室 [2]中国科学院研究生院,北京100049

出　　处：《物理化学学报》2006年第12期1445-1450,共6页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(50272070)资助项目

摘　　要：以含有Fe3+/Fe2+离子对的H2SO4溶液为电解液,以多孔炭做电极材料,就Fe3+/Fe2+离子对在多孔炭纳米孔隙中的电化学行为及准电容效应进行了探讨.循环伏安测试结果表明,Fe3+/Fe2+离子对在多孔炭电极纳米孔隙中发生了可逆的电化学反应.恒流充放电结果发现,加入Fe3+/Fe2+使得充放曲线出现对称的充放电平台,有效地提高了电化学电容器(EC)的电能存储容量,其单电极比电容最高达174 mAh·g-1,比单纯的H2SO4电解液的比电容高109 mAh·g-1,且有着良好的循环稳定性.根据实验现象及结果,探讨了Fe3+/Fe2+离子对在EC电极上的充放电机理,并提出了一种新的概念——氧化还原电解液电化学电容器.The electrochemical characteristics and pseudocapacitive effects of Fe^3＋/Fe^2＋ ion pair were investigated in an electrochemical capacitor （EC） system using porous carbon as electrode material and with H2SO4 solution containing Fe^3＋/Fe^2＋ ion pair as electrolyte. The cyclic voltammetric results indicated that highly reversible electrochemical redox reactions of Fe^3＋/Fe^2＋ ion pair occurred within the nano-pore structures of the porous carbon electrodes. Symmetrical charge/discharge cycles were achieved due to the existence of Fe^3＋/Fe^2＋ ion pair, which effectively improved the capacity of the electrochemical capacitor system. Apart from its excellent cyclic stability, the specific capacitance of the single electrode system reached 174 mAh·g^-1, which is 109 mAh·g^-1 higher than that obtained for H2SO4 as the electrolyte. The charge/discharge mechanism of Fe^3＋/Fe^2＋ ion pair in the EC systems was discussed and a new type of redox electrolyte electrochemical capacitor was suggested.

关 键 词：电化学电容器 法拉第准电容 多孔炭 Fe^3+/Fe^2+离子对 电吸附 

分 类 号：TM53[电气工程—电器]