Two-step hydrothermal process for synthesis of F-doped BiVO4 spheres with enhanced photocatalytic activity

F-doped BiVO4 spheres were synthesized by a simple two step hydrothermal process. The effects of F ions on the microstructure and photocatalytic activity of BiVO4 were investigated in detail. The undoped BiVO4 solid spheres with smooth surface are chemically etched by corrosive F− ions, which result in the F-doped BiVO4 spheres with large pores on the surface. The substitution of O2− ions by F− ions could result in the decrease of the BiVO4 lattice parameters, influence the chemical environment surrounding the Bi, V and O elements, cause the red-shifted of the adsorption edge and modify the absorption abilities in visible light region. F-doped BiVO4 spheres exhibited higher photocatalytic activity than undoped BiVO4 under visible light irradiation because an appropriate amount of F− ions introduced into BiVO4 crystal lattice might effectively restrain the recombination of photogenerated electron–hole pairs.