Structural, optical and photocatalytic properties of new solid photocatalysts, BixIn1−xTaO4 (0 < x < 1)

The BixIn1−xTaO4 (0 < x < 1) photocatalysts were synthesized by solid-state reaction and characterized by powder X-ray diffraction. Rietveld structure refinement revealed that the variation of x in the BixIn1−xTaO4 photocatalysts could cause the change in crystal structure. The structure of the Bi0.2In0.8TaO4 photocatalyst is monoclinic system with space group P2/a. However, the structure of the BixIn1−xTaO4 (x = 0.5 and 0.8) photocatalysts is triclinic system with space group P-1. The band gaps of the BixIn1−xTaO4 (x = 0.2, 0.5 and 0.8) photocatalysts were estimated to be about 2.86, 2.71 and 2.74 eV, respectively. Under visible light irradiation (λ > 420 nm), H2 and O2 were evolved using the BixIn1−xTaO4 photocatalysts from CH3OH/H2O and AgNO3/H2O solutions, respectively. The Bi0.5In0.5TaO4 photocatalyst showed the highest activity compared with that of the BixIn1−xTaO4 (x = 0.2 and 0.8) photocatalysts.