电化学2017，Vol.23Issue(6)：684-693,10.DOI:10.13208/j.electrochem.161215
离子液体电解质种类对活性炭电极超级电容器电化学性能的影响
Engineering the Electrochemical Capacitive Properties of Activated Carbons by Correct Selection of Ionic-Liquid Electrolytes
摘要
Abstract
In order to improve the electrochemical capacitive properties and to apply coconut shell activated carbon (AC) serving as electrode materials in ionic liquid (IL)-based supercapacitor (SC),the coconut shell AC material was re-activated using a steam as an activating agent in this work,forming a secondary AC (W-AC).The results showed that the specific capacitance of the W-AC electrode was much larger than that of the raw activated carbon electrode (R-AC) in 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4).The electrochemical techniques including cyclic voltammetry (CV),galvanostatic charge/discharge (GCD) measurement,and electrochemical impedance spectroscopy (EIS) were used to systematically study the capacitive properties of W-AC electrode in a series of ILs composed of different cations and anions.The electrochemical performances of the W-AC electrode using different ILs as electrolytes varied because of the different ion diameters,liquid viscosities and ionic conductivities for various ILs.Among them,the IL electrolytes composed of EMIM+,BMIM+ and BF4-,TFSI-were found to be most suitable for W-AC electrode.The specific capacitance of W-AC electrode reached 153 F ·g-1 in [EMIM]BF4 IL electrolyte,and the as-assembled SCs could achieve a high energy density of 57 Wh· kg-1 with a potential window of 3.5 V in [BMIM]BF4.These results may provide valuable information for selecting appropriate ionic liquids and designing high-performance supercapacitors to meet different needs.关键词
椰壳活性炭/超级电容器/离子液体Key words
coconut shell activated carbon/supercapacitors/ionic liquids分类
化学化工引用本文复制引用
张秋红,申保收,左宋林,卫歆雨..离子液体电解质种类对活性炭电极超级电容器电化学性能的影响[J].电化学,2017,23(6):684-693,10.基金项目
林业公益性行业科研专项(No.201404611)及教育部博士点博导基金(No.20133204110007)资助 （No.201404611）
