Acta Phys. -Chim. Sin. ›› 2002, Vol. 18 ›› Issue (01): 21-25.doi: 10.3866/PKU.WHXB20020105

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Photocatalytic Mechanism Studies of TiO2 Particulate Suspension by IntensityModulation Photocurrent Spectroscopy

Yin Feng;Lin Yuan;Lin Rui-Feng;Xiao Xu-Rui   

  1. Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080
  • Received:2001-06-28 Revised:2001-08-31 Published:2002-01-15
  • Contact: Xiao Xu-Rui

Abstract: The mechanism of the photocatalytic processes of TiO2 particulate suspension was studied in a PEC cell by using IntensityModulated Photocurrent Spectroscopy (IMPS). Collecting the frequency dependent photocurrent response from the TiO2 particulate suspension under modulated irradiation on a Pt electrode, a complex plane of IMPS response was obtained. The upper and lower semicircles represent the cathodic reduction and anodic oxidization reaction processes of photogenerated holes and electrons, respectively. The photocatalytic mechanism and the effects of applied potentials and the addition of H2O2 were discussed in terms of the amplitude of cathodic and anodic photocurrents and the characteristic frequencies of upper and lower semicircles.

Key words: IntensityModulated Photocurrent Spectroscopy(IMPS),   Photocatalysis of TiO2 particulate suspension, Photogenerated charges, Anodic photocurrents, Cathodic photocurrents