化学学报 ›› 2006, Vol. 64 ›› Issue (17): 1824-1830. 上一篇    下一篇

研究论文

蒽醌在乙二醇/Triton X胶束与乙二醇/三乙胺溶液中光还原的时间分辨电子自旋共振研究

陆同兴*,1; 许新胜1; 洪新1; 李干佐2   

  1. (1安徽师范大学原子与分子物理研究所 芜湖 241000)
    (2山东大学胶体与界面化学教育部重点实验室 济南 250100)
  • 投稿日期:2005-09-21 修回日期:2006-05-08 发布日期:2006-09-14
  • 通讯作者: 陆同兴

TR-ESR Study on Photoreduction of Anthraquinone in Ethylene Glycol/Triton Micelle and Ethylene Glycol/Triethylamine Solutions

LU Tong-Xing*,1; XU Xin-Sheng1; HONG Xin1; LI Gan-Zuo2   

  1. (1 Atom and Molecular Institute, Anhui Normal University, Wuhu 241000)
    (2 Key Laboratory for Colloid and Interface Chemistry of the Ministry of Education of China, Shandong University, Jinan 250100)
  • Received:2005-09-21 Revised:2006-05-08 Published:2006-09-14
  • Contact: LU Tong-Xing

用时间分辨电子自旋共振研究了乙二醇/Triton X 胶束与乙二醇/三乙胺溶液中蒽醌(AQ)的光还原. 在蒽醌/乙二醇/Triton X/H2O胶束中, 获得蒽半醌自由基AQH的很强的TR-ESR信号, 并检测到一定强度的负离子基AQ•- TR-ESR信号. 在蒽醌/乙二醇/三乙胺/H2O体系中同时有较强的AQH与AQ•-的TR-ESR信号. 分析并讨论了蒽醌在两种体系中的还原过程. 根据CIDEP的强度与Triton X及三乙胺浓度的关系, 推求了三线态3AQ*对自由基AQH的反应速率常数. 根据化学诱导动态电子极化(CIDEP)信号随时间的变化, 计算了AQH的CIDEP弛豫时间.

关键词: 化学诱导动态电子极化, 蒽半醌自由基, 蒽醌负离子基, 三乙胺, 表面活性剂

The photoreduction of anthraquinone in the ethylene glycol/Triton micelle and ethylene glycol/triethylamine solution was studied with the time resolved electron spin resonance (TR-ESR) spectroscopy. The very strong TR-ESR signal of the semianthraquinone radical AQH, formed from the hydrogen transfer from Triton X to 3AQ, was recorded in the ethylene glycol/Triton micelle, and the TR-ESR signal of the anthraquinone anion radical AQ•- was also detected in this micelle system. The significant TR-ESR signals of semianthraquinone radical AQH and anthraquinone anion radical AQ•- were obtained simultaneously in the anthraquinone/ethylene glycol/triethylamine system through two separate paths. The semianthraquinone radical AQH was generated through hydrogen transfer reaction from triethylamine, while anthraquinone anion radical AQ•- was produced through electron transfer reaction and the triethylamine was the donor. Based on the experimental results mentioned above, the photoreduction processes of anthraquinone in these two systems were analyzed in detail. At the same time, the reaction rate constants of the triplet 3AQ* to radical AQH were deduced according to the dependence of CIDEP (chemically induced dynamic electron polarization) intensity on the concentration of Triton X and triethylamine. Furthermore, the relaxation time of radical AQH was also calculated from its time dependent CIDEP signal.

Key words: chemically induced dynamic electron polarization, semianthraquinone radical, anthraquinone anion radical, triethylamine, surfactant