Measurements of differential capacitance in room temperature ionic liquid at mercury, glassy carbon and gold electrode interfaces
Measurements of differential capacitance in room temperature ionic liquid at mercury, glassy carbon and gold electrode interfaces
复制标题
DOI：
10.1016/j.elecom.2007.07.009
复制
发表时间：
2007-09-01
影响因子：
5.4
通讯作者：
Ohsaka, Takeo
中科院分区：
文献类型：
--
作者：
Alam, Muhammad Tanzirul;Islam, Md. Mominul;Ohsaka, Takeo
测量了1-丙基-3-甲基咪唑四氟硼酸盐（PMIBF 4）离子液体在3种不同电极基底（Hg、GC（玻碳）和Au）上的微分电容随电位的变化。在不同的电极上得到了本质上不同的电容-电位曲线。从在PMIBF 4中滴汞电极处测量的抛物线电毛细管曲线，发现零电荷电位（PZC）为-0.31V vs. Ag/AgCl（线）。然而，发现Hg电极处的电容-电位曲线未显示与PZC相关的任何谷，而在GC和An电极处分别在0.29和-0.51 V处观察到最小值。这与最近的理论研究结果不一致，即电容-电位曲线应呈钟形，在PZC处电容最大。首次在GC电极上观察到了与无机熔盐类似的抛物线电容-电位曲线。本文还讨论了它们的电容-电位曲线不同的可能原因。(c)2007 Elsevier B. V.保留所有权利。
Differential capacitances were measured in l-propyl-3-methylimidazolium tetrafluoroborate (PMIBF4) ionic liquid at three different electrode substrates (Hg, GC (glassy carbon) and Au) as a function of potential. Essentially different capacitance-potential curves were obtained at different electrodes. From the parabolic electrocapillary curve measured at dropping Hg electrode in PMIBF4, the potential of zero charge (PZC) was found to be -0.31 V vs. Ag/AgCl (wire). However, the capacitance-potential curve at Hg electrode was found not to show any valley related to the PZC, whereas at GC and An electrodes a minimum was observed at 0.29 and -0.51 V, respectively. The results are in disagreement with the recent theoretical study which implies that the capacitance-potential curve should be of bell shape with the maximum value of capacitance at PZC. The parabolic capacitance-potential curve similar to those obtained in inorganic molten salts was also observed for the first time at GC electrode. Probable causes of the difference in their capacitance-potential curves were also discussed. (c) 2007 Elsevier B.V. All rights reserved.