Hydrogenation and Ammoniation of SrTiO3 for an Enhanced Visible-light Photocatalysis

Hydrogenation and ammoniation of SrTiO₃ (STO), a normal ultraviolet photocatalyst, were performed by annealing STO〈100〉in H₂:N₂=5%:95% and NH₃, respectively, at various tem-peratures T. It was found that hydrogenation at T≥900 oC remarkably enhanced the UV photocatalytic ability of STO, but the visible-light photocatalysis was still unavailable, while ammoniation at T≥800 oC introduced the N doping, resulting in visible-light photocat-alytic activity. Furthermore, when a hydrogenated STO was subjected to ammoniation, the visible-light photocatalytic ability was nearly the same as that of the ammoniated one; but the hydrogenation of an ammoniated one significantly enhanced visible-light photocatalysis, indicating a synergetic effect of hydrogenation and ammoniation. Discussions and identifi-cations have been made to analyze these results.