Photophysical and photocatalytic properties of Sr2(Ta1-XNbX)2O7 with layered perovskite structure were studied to explore the possibility of energy structure control by making a solid solution. The band gap of Sr2(Ta1-XNbX)2O7 was decreased as the ratio of niobium to tantalum was increased. The Sr2(Ta1-XNbX)2O7 solid solution photocatalysts loaded with NiO co-catalysts decomposed water into H2 and O2 in a stoichiometric ratio. A NiO/Sr2Ta2O7 photocatalyst showed the highest activity. The photocatalytic activity was drastically decreased by substitution of a small amount of niobium (X=0.05) for tantalum. However, a Sr2(Ta0.75Nb0.25)2O7 photocatalyst showed a relatively high activity among the solid solutions of Sr2(Ta1-XNbX)2O7(0<X<1). The activities of Sr2(Ta1-XNbX)2O7 solid solution photocatalysts depended on the conduction band level and the efficiency of non-radiative recombination between photogenerated electron-hole pairs.
|ジャーナル||Journal of Photochemistry and Photobiology A: Chemistry|
|出版ステータス||Published - 2001 11 29|
ASJC Scopus subject areas
- 化学 (全般)