New type of BiPO(4) oxy-acid salt photocatalyst with high photocatalytic activity on degradation of dye.

A high photocatalytic BiPO(4) with a novel nonmetal oxy acid structure is synthesized by a hydrothermal method. BiPO(4) photocatalyst has an optical indirect band gap of 3.85 eV. In a comparison of BiPO(4) with that of TiO(2) (P25, Degussa), it is found that the photocatalytic activity of BiPO(4) is twice that of TiO(2) (P25, Degussa) for the degradation of methylene blue (MB) dye, while the BET surface of BiPO(4) is just one tenth of that of P25. Both the high position of the valence band and the high separation efficiency of electron-hole pairs result in the high photocatalytic activity. The inductive effect of PO(4)(3-) helps the e(-)/h(+) separation, which plays an important role in its excellent photocatalytic activity. It may extend to the synthesis of other inorganic nonmetal salts of oxy photocatalysts with suitable band gap and high activity for the environmental purification of organic pollutants in aqueous solution.