title: Towards understanding the color change of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide during gamma irradiation: an experimental and theoretical study.
abstract: The application of room-temperature ionic liquids (RTILs) in nuclear spent fuel recycling requires a comprehensive knowledge of radiation effects on RTILs. Although preliminary studies indicate a relatively high radiation stability of RTILs, little attention is paid to the color change of RTILs, an obvious phenomenon of RTILs during irradiation. In this paper, we have investigated radiation-induced darkening and decoloration of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIm][NTf2]), an ionic liquid representing the most popular class of RTILs, by means of UV-Vis analysis and time-dependent density functional theory calculations. Based on the experimental and computational results, it is proposed that the color change of [BMIm][NTf2] upon irradiation originates from the formation of double bonds in the aliphatic chains of pristine organic cations (or radiolytic products of RTILs) and various associated species containing these "double-bond products". This work sheds light on the understanding of the radiation-induced color change of RTILs.
authors: Beijing National Laboratory for Molecular Sciences, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, 100871, Beijing, P. R. China. mlzhai@pku.edu.cn.
authors: Shuojue
authors: S
authors: Wang
authors: Junzi
authors: J
authors: Liu
authors: Liyong
authors: L
authors: Yuan
authors: Zhenpeng
authors: Z
authors: Cui
authors: Jing
authors: J
authors: Peng
authors: Jiuqiang
authors: J
authors: Li
authors: Maolin
authors: M
authors: Zhai
authors: Wenjian
authors: W
authors: Liu