Effects of Acceptor Doping to KTaO3 on Photocatalytic Decomposition of Pure H2O

It was found for the first time that controlling the charge density in oxide semiconductors with an acceptor was effective for improving the activity to photolysis of H 2 O. Although the photodecomposition activity of NiO supported on nondoped KTaO 3 was negligibly small, doping small amount of acceptors such as tri- or tetravalent cations to KTaO 3 increased the formation rate of H 2 and O 2 . In particular, it was found that NiO supported on KTaO 3 doped with 8 mol % Zr 4+ exhibits higher activity to the photocatalytic decomposition of H 2 O than that of a well-known photocatalyst of Pt/TiO 2 .