Structural and photocatalytic properties of novel Bi2GaVO7

Bi2GaVO7 was synthesized by solid-state reaction method for the first time and its structural and photocatalytic properties were investigated. The results indicated that this compound crystallizes in the tetragonal crystal system with space group I4/mmm. In addition, the band gap of Bi2GaVO7 was estimated to be about 2.13(8) eV. For the photocatalytic water splitting reaction, H2 or O2 evolution was observed from pure water with Bi2GaVO7 as the photocatalyst under ultraviolet light irradiation. Photocatalytic degradation of aqueous methylene blue (MB) dye over this compound was further investigated under visible light irradiation. Bi2GaVO7 showed notable higher catalytic activity compared to P-25 for MB photocatalytic degradation under visible light irradiation. Complete removal of aqueous MB was observed after visible light irradiation for 170 min with Bi2GaVO7 as the photocatalyst. The decrease of the total organic carbon (TOC) and the formation of inorganic products, SO42− and NO3−, demonstrated the continuous mineralization of aqueous MB during the photocatalytic process.