摘要
采用激光闪光光解-瞬态吸收光谱技术研究了355nm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260nm、激发三线态(PyTS3*)在300nm及阴离子自由基(PyTS-?)在330nm处的特征吸收峰;分析了生成的水合电子(e-aq)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′105s-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.
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（PyTS 1＊ ）at 260 nm,the excited triplet（PyTS 3＊ ）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 （e - aq ）,and the pseudo-first-order rate constant of hydrated electrons with PyTS was determined to be 2.7′ 10 5 s ？1 .The quantum yield of e - aq generated via two-photon ionization of PyTS was computed to be 3.2′10 ？2 under these conditions.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2012年第4期957-962,共6页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(20777012)
教育部博士点基金(200802460006)资助项目~~
关键词
激光闪光光解
自由基
水合电子
量子产率
瞬态吸收
Laser flash photolysis
Free radical
Hydrated electron
Quantum yield
Transient absorption
