Photocatalytic activity of a sillenite-type material Bi25GaO39

Sillenite-type Bi25GaO39 as an efficient photocatalyst was studied in the present paper. The compound synthesized by a solid state reaction method has a band gap of 2.95 eV. It possesses a fair visible-light-response ability. The UV-light-induced photocatalytic activities for degrading methylene blue follow the decreasing order of anatase TiO2 > Bi25GaO39 > Bi12GeO20 > Bi24Ga2O39, different from Bi12GeO20 > Bi25GaO39 > Bi24Ga2O39 > TiO2 under visible light irradiation. The dispersion of Pt over Bi25GaO39 leads to an obvious increase in photocatalytic performance. The opener structure of Bi25GaO39 is proposed to explain the higher UV-light-induced photocatalytic activity, compared with Bi24Ga2O39 and Bi12GeO20.