Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (04): 957-962.doi: 10.3866/PKU.WHXB201202203

• PHOTOCHEMISTRY AND RADIATION CHEMISTRY • Previous Articles     Next Articles

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
  • 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).

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