Photocatalytic oxidation of water on TiO2-coated WO3 particles by visible light using Iron(III) ions as electron acceptor

Photocatalytic oxidation of water on TiO2-coated WO3 particles was studied using iron(III) ions as the electron acceptor with the aim of constructing a photochemical energy conversion system. Although WO3 photocatalysts can utilize part of visible light, the reaction was decelerated as the concentration of iron(II) ions in solution increased. This was a marked contrast with the reaction using TiO2 photocatalysts, whose photocatalytic activity is scarcely affected by iron(II) ions in solution. In order to modify the surface of WO3 particles, they were coated with a thin TiO2 layer. Using such photocatalysts, the harmful effect by iron(II) ions on the WO3 photocatalyst was restrained to some extent, and the efficiency of photooxidation of water by visible Light was improved. (C) 1998 Elsevier Science S.A. All rights reserved.