Visible Light-Driven BiVO4/TiO2 Composite Photocatalysts: Preparation Methods and Photocatalytic Performance

BiVO4/TiO2 composite photocatalysts were successfully synthesised via different methods, and the physical and photophysical properties of the as-prepared photocatalysts were fully characterised by X-ray diffraction, scanning electron microscopy, field-emission transmission electron microscopy, energy dispersive spectroscopy, UV-vis diffuse reflectance spectroscopy, photoluminescence spectroscopy and Brunauer–Emmett–Teller (BET) surface area analysis. Methylene blue was selected as model pollutant to investigate the photocatalytic activity of BiVO4/TiO2 composite materials. The results reveal that BiVO4/TiO2 fabricated by different methods exhibits higher photocatalytic activity than pure BiVO4 and TiO2, and the coprecipitated BiVO4/TiO2 composite shows the best photocatalytic activity. The diffuse reflectance spectroscopy results demonstrated that the 20 wt-% coprecipitated BiVO4/TiO2 exhibited a significant, broad spectrum response not only between 400 and 500 nm but also from 500 to 800 nm wavelength.