Large impact of strontium substitution on photocatalytic water splitting activity of BaSnO3

The effects of Sr substitution for Ba on photocatalytic water splitting activity of BaSnO3 were investigated experimentally and theoretically. The chemical incorporation of Sr into BaSnO3 induced a great enhancement for H-2 production. Density function theory calculations of Ba1-xSrxSnO3 (x=0, 0.5, and 1.0) reveal that the bottom of the conduction band is gradually pushed up and the contribution of the Sr 5s orbitals to the bottom of the conduction band gradually becomes dominant with the increase of Sr concentration from x=0 to x=1.0. The participation of the normally inert Sr cation in the electronic structure of the SnO32- framework not only enhances the reduction ability of photoinduced electrons but also provides favorable opportunities for charge carrier transport, thus enhancing the photocatalytic activity of BaSnO3. (c) 2007 American Institute of Physics.