物理化学学报 >> 2014, Vol. 30 >> Issue (5): 987-993.doi: 10.3866/PKU.WHXB201403112

光化学和辐射化学 上一篇    下一篇

IR125和HDITCP在不同烷基链长阳离子离子液体中的光异构化动力学

袁树威, 吕荣, 于安池   

  1. 中国人民大学化学系, 北京100872
  • 收稿日期:2014-01-13 修回日期:2014-03-11 发布日期:2014-04-25
  • 通讯作者: 于安池 E-mail:a.yu@chem.ruc.edu.cn
  • 基金资助:

    国家自然科学基金(21273280)资助项目

Photoisomerization Kinetics of IR125 and HDITCP in Ionic Liquids with Different Cation Alkyl Chain Lengths

YUAN Shu-Wei, LÜ Rong, YU An-Chi   

  1. Department of Chemistry, Renmin University of China, Beijing 100872, P. R. China
  • Received:2014-01-13 Revised:2014-03-11 Published:2014-04-25
  • Contact: YU An-Chi E-mail:a.yu@chem.ruc.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21273280).

摘要:

利用稳态吸收和荧光光谱以及时间相关单光子计数实验,分别测得近红外花菁分子IR125和HDITCP在不同烷基链长阳离子离子液体中的荧光量子产率和荧光寿命,并通过计算获得了它们各自在相应离子液体中的光异构化速率. 发现IR125 和HDITCP在不同离子液体中的光异构化速率没有随着离子液体粘度的增大而产生明显变化. 与IR125和HDITCP在与离子液体具有相同粘度的甘油水溶液中的光异构化速率对比,发现IR125和HDITCP在离子液体中的光异构化能垒比它们在甘油水溶液中的光异构化能垒增大约2 kJ·mol-1,这表明在高粘度的离子液体中IR125或HDITCP与离子液体之间特殊的相互作用会阻碍它们各自的光异构化过程.

关键词: 花菁染料, 离子液体, 光异构化, 荧光量子产率, 荧光寿命

Abstract:

The photoisomerization kinetics of IR125 and HDITCP in ionic liquids with different cation alkyl chain lengths were investigated by measuring their fluorescence lifetimes and quantum yields using steady-state absorption and fluorescence spectroscopies, and time-correlated single-photon counting experiments. It was found that the photoisomerization rate constants for IR125 and HDITCP in all the selected ionic liquids were almost identical and did not change with increasing ionic liquid viscosity. A comparison of the photoisomerization rate constants of IR125 and HDITCP in isoviscous aqueous glycerol solutions with those in ionic liquids showed that the photoisomerization energy barriers of IR125 and HDITCP in ionic liquids were about 2 kJ·mol-1 higher than those in the isoviscous aqueous glycerol solutions, indicating that specific interactions between IR125 or HDITCP and the ionic liquid restrain their respective photoisomerization processes in highly viscous ionic liquids.

Key words: Cyanine dye, Ionic liquid, Photoisomerization, Fluorescence quantum yield, Fluorescence lifetime

MSC2000: 

  • O644