A new DMF-derived ionic liquid with ultra-high conductivity for high-capacitance electrolyte in electric double-layer capacitor
A new DMF-derived ionic liquid with ultra-high conductivity for high-capacitance electrolyte in electric double-layer capacitor
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DOI：
10.1016/j.electacta.2019.07.015
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发表时间：
2019-10-01
影响因子：
6.6
通讯作者：
Zhang, Shiguo
中科院分区：
文献类型：
--
作者：
Chen, Zhengjian;Li, Zuopeng;Zhang, Shiguo
本研究制备了一种新型DMF衍生的离子液体电解质[EDMF] BF 4，并对其进行了表征，将其作为高容量电解质应用于双电层电容器（EDLC）。[EDMF] BF 4被测量为具有非常高的离子电导率和低粘度（在25 ℃下为24.8 mS cm（-1）和21.6 mPa s），以及与[EMIm] BF 4相当的电化学窗口（4.4 V，在GC电极上），[EMIm] BF 4是最广泛研究的具有高性能的离子液体电解质之一。因此，[EDMF] BF 4被用作活性炭基EDLC的非挥发性电解质。基于[EDMF] BF 4的EDLC能够在2.7 V的电压下稳定运行，活性炭的比电容量测定为165 F g（-1）（在1 mA cm（-2）和30 ° C下第100次循环），这比[EMIm] BF 4的情况（126 F g（-1））大得多。此外，[EDMF] BF 4在EDLC中显示出比[EMIm] BF 4更低的欧姆电阻和双电层电阻。[EDMF] BF 4电解质的高性能应与中等尺寸的准线性[EDMF]阳离子有关，这可能更适合于增强的离子迁移率和紧凑的双电层。(C)2019爱思唯尔有限公司版权所有。
In this study, a new DMF-derived ionic liquid electrolyte [EDMF]BF4 was prepared, characterized and applied as a high-capacitance electrolyte for electric double-layer capacitors (EDLCs). [EDMF]BF4 was measured to have very high ionic conductivity and low viscosity (24.8 mS cm(-1) and 21.6 mPa s at 25 degrees C), as well as a comparable electrochemical window (4.4 V, on a GC electrode) with [EMIm]BF4, which is one of the most widely studied ionic liquid electrolytes with high performance. Therefore, [EDMF]BF4 was used as a non-volatile electrolyte for activated carbon-based EDLCs. The [EDMF]BF4-based EDLCs are capable to operate stably over a voltage of 2.7 V, and the specific capacitance of activated carbon was determined to be 165 F g(-1) (100th cycle at 1 mA cm(-2) and 30 degrees C), which is much larger than in the case of [EMIm]BF4 (126 F g(-1)). Besides, [EDMF]BF4 showed lower ohmic resistance and double layer resistance than [EMIm]BF4 in EDLCs. The high performance of [EDMF]BF4 electrolyte should be related to the quasi-linear [EDMF] cation of moderate size, which is presumably more suitable for enhanced ion mobility and compact electric double layer. (C) 2019 Elsevier Ltd. All rights reserved.