文献类型：期刊文献

英文题名：Effect of Alkyl Chain Length of Imidazolium Cation on the Electroreduction of CO2 to CO on Ag Electrode in Acetonitrile

作者：Wang, Qianqian[1];Chen, Chengzhen[1];Zhong, Juhua[2];Zhang, Bo[2];Cheng, Zhenmin[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Dept Phys, Coll Sci, Shanghai 200237, Peoples R China

年份：2017

卷号：70

期号：3

起止页码：293

外文期刊名：AUSTRALIAN JOURNAL OF CHEMISTRY

收录：;EI(收录号：20171003423926);WOS:【SCI-EXPANDED(收录号:WOS:000395561500010)】；

基金：Financial support from the Fundamental Research Funds for the Central Universities is gratefully acknowledged.

语种：英文

外文关键词：Computation theory - Electrodes - Chain length - Density functional theory - Efficiency - Electrolytic reduction - Ionic liquids - Silver - Carbon dioxide - Positive ions

摘要：The effect of imidazolium-based ionic liquid on the electroreduction of CO2 to CO over a Ag electrode in acetonitrile catholyte was investigated. The voltage-current profiles clearly indicate that the electroreduction of CO2 is sensitive to the alkyl chain length at the N1-position in imidazolium cation (MIM+). Density functional theory computation suggests that the onset potential of CO2 reduction is related to the association degree between MIM+ and CO2 center dot- species. More importantly, preparative scale electrolysis shows that the selectivity and output rate for the target product CO are also significantly affected by MIM+. With the elongation of the alkyl group in MIM+ from ethyl to octyl, the Faradaic efficiency for CO remarkably increases from 87 +/- 4% to 97 +/- 2% and then remains almost unchanged. However, the curve of the current density with respect to the chain length of alkyl group shows a convex style. These results indicate the dependence of CO2 reduction efficiency on the MIM+ adsorbed on the Ag electrode surface.