Effects of Fluorination and Molybdenum Codoping on Monoclinic BiVO(4) Photocatalyst by HSE Calculations

[Image: see text] Monoclinic phase bismuth vanadate (BiVO(4)) is one of the most promising photoelectrochemical materials used in water-splitting photoelectrochemical cells. It could be even better if its band gap and charge transport characteristics were optimized. Although codoping of BiVO(4) has proven to be an effective strategy, its effects are remarkably poorly understood. Using the Heyd–Scuseria–Ernzerhof (HSE) hybrid functional, we estimate the formation energy, electronic properties, and photocatalytic activities of F and Mo codoped BiVO(4). We find that Mo atoms prefer to replace V atoms, whereas F atoms prefer to replace O atoms (F(O)Mo(V)-doped BiVO(4)) under oxygen-poor conditions according to calculated formation energies. BiVO(4) doped with F(O)Mo(V) is found to be shallow-level doped, occurring with some continuum states above the conduction band edge, which is advantageous for photochemical catalysis. Moreover, F(O)Mo(V)-doped BiVO(4) shows absorption stronger than that of pure BiVO(4) in the visible spectrum. Based on the band-edge calculation, BiVO(4) doped with F(O)Mo(V) still retains a high oxidizing capacity. It has been shown that F(O)Mo(V)-doped BiVO(4) exhibits a very high photocatalytic activity under visible light.