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.

Keywords: IntensityModulated Photocurrent Spectroscopy(IMPS)   　 Photocatalysis of TiO₂ particulate suspension   Photogenerated charges   Anodic photocurrents   Cathodic photocurrents  
Received: 2001-06-28 Accepted: 2001-08-31 Publication Date (Web): 2002-01-15
Corresponding Authors: Xiao Xu-Rui Email: G211@IPC.AC.cn


Cite this article: Yin Feng;Lin Yuan;Lin Rui-Feng;Xiao Xu-Rui. Photocatalytic Mechanism Studies of TiO₂ Particulate Suspension by IntensityModulation Photocurrent Spectroscopy[J]. Acta Phys. -Chim. Sin., 2002,18 (01): 21-25.    doi: 10.3866/PKU.WHXB20020105