Preparation, characterization and photocatalytic activity of transition metal-loaded BiVO4

The Fe-, Co- and Cu-loaded BiVO4 were synthesized by wet impregnation method. The physical and photophysical properties of the samples were characterized by ICP-OES, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis diffused reflectance spectroscopy (DRS), photoluminescence (PL) and specific surface area. The XRD analysis confirmed that all photocatalysts had the same crystal forms with the single monoclinic scheelite structure. The results showed that Fe2O3, Co3O4 and CuO existed on the surface of M-BiVO4 catalysts (M = Fe, Co and Cu), respectively. The red-shifted trend of absorption band by DRS studies was as follows: Co-BiVO4 > Cu-BiVO4 > Fe-BiVO4 > pure BiVO4. The observed trends for the PL intensities of M-BiVO4 were Co-BiVO4 > Fe-BiVO4 > Cu-BiVO4. The influence of different transition metal oxides loading (Fe2O3, Co3O4 and CuO) on the photocatalytic activity for photocatalytic decolorization of methylene blue (MB) was discussed under UV and visible light irradiation. It is found that Cu-loaded BiVO4 showed the highest reaction activity among all transition metal oxides-loaded samples.