文献类型：期刊文献

英文题名：Impurity Effects on Charging Mechanism and Energy Storage of Nanoporous Supercapacitors

作者：Lian, Cheng[1,2];Liu, Kun[3,4];Liu, Honglai[1,2];Wu, Jianzhong[3,4]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[3]Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA;[4]Univ Calif Riverside, Dept Environm Engn, Riverside, CA 92521 USA

年份：2017

卷号：121

期号：26

起止页码：14066

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY C

收录：;EI(收录号：20172903946423);WOS:【SCI-EXPANDED(收录号:WOS:000405252800012)】；

基金：This research was sponsored by the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. C.L. and H.L. thank the financial support by the National Natural Science Foundation of China (No. 91334203) and the 111 Project of China (No. B08021). The numerical calculations were performed at the National Energy Research Scientific Computing Center (NERSC).

语种：英文

外文关键词：Ionic liquids - Impurities - Electrodes - Density functional theory

摘要：Room-temperature ionic liquids (RTILs) have been widely used as electrolytes to enhance the capacitive performance of electrochemical capacitors also known as supercapacitors. Whereas impurities are ubiquitous in RTILs (e.g., water, alkali salts, and organic solvents), little is known about their influences on the electrochemical behavior of electrochemical devices. In this work, we investigate different impurities in RTILs within the micropores of carbon electrodes via the classical density functional theory (CDFT). We find that under certain conditions impurities can significantly change the charging behavior of electric double layers and the shape of differential capacitance curves even at very low concentrations. More interestingly, an impurity with a strong affinity to the nanopore can increase the energy density beyond a critical charging potential. Our theoretical predictions provide further understanding of how impurity in RTILs affects the performance of supercapacitors.