物理化学学报 >> 2012, Vol. 28 >> Issue (04): 957-962.doi: 10.3866/PKU.WHXB201202203

光化学和辐射化学 上一篇    下一篇

芘四磺酸钠水溶液激光闪光光解机理

袁海霞1,2, 潘沪湘2, 吴彦霖1, 赵建丰1, 董文博1   

  1. 1. 复旦大学环境科学与工程系, 上海 200433;
    2. 海军医学研究所, 上海 200433
  • 收稿日期:2011-11-04 修回日期:2012-01-31 发布日期:2012-03-21
  • 通讯作者: 董文博 E-mail:wbdong@fudan.edu.cn
  • 基金资助:

    国家自然科学基金(20777012)和教育部博士点基金(200802460006)资助项目

Laser Flash Photolysis Mechanism of Pyrenetetrasulfonate in Aqueous Solution

YUAN Hai-Xia1,2, PAN Hu-Xiang2, WU Yan-Lin1, ZHAO Jian-Feng1, DONG Wen-Bo1   

  1. 1. Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, P. R. China;
    2. Institute of Naval Medicine, Shanghai 200433, P. R. China
  • Received:2011-11-04 Revised:2012-01-31 Published:2012-03-21
  • Contact: DONG Wen-Bo E-mail:wbdong@fudan.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20777012) and Doctoral Fund of Ministry of Education of China (200802460006).

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摘要： 采用激光闪光光解-瞬态吸收光谱技术研究了355 nm激光作用下芘四磺酸钠(PyTS)水溶液的光化学反应机理及其产生水合电子的动力学行为. 研究首次发现PyTS水溶液激发单线态(PyTS1*)在260 nm、激发三线态(PyTS3*)在300 nm及阴离子自由基(PyTS-·)在330 nm处的特征吸收峰; 分析了生成的水合电子(eaq-)的主要反应途径包括自猝灭反应及与PyTS的反应, 得到水合电子与PyTS反应的准一级速率常数为2.7×105 s-1; 并计算得到在此实验条件下, PyTS水溶液经双光子吸收产生的水合电子量子产率为3.2×10-2.

关键词: 激光闪光光解, 自由基, 水合电子, 量子产率, 瞬态吸收

Abstract: The mechanism of photochemical reactions of pyrenetetrasulfonate (PyTS) in aqueous solution was studied using laser flash photolysis-transient absorption spectrum techniques under irradiation at 355 nm. The characteristic absorption peaks of the excited singlet (PyTS1*) at 260 nm, the excited triplet (PyTS3*) at 300 nm, and the anion radical (PyTS-·) at 330 nm were first confirmed. Self-quenching and reaction with PyTS were regarded as the main decay channels for hydrated electrons (eaq-), and the pseudo-first-order rate constant of hydrated electrons with PyTS was determined to be 2.7× 105 s-1. The quantum yield of eaq- generated via two-photon ionization of PyTS was computed to be 3.2×10-2 under these conditions.

Key words: Laser flash photolysis, Free radical, Hydrated electron, Quantum yield, Transient absorption