Structural and electronic properties of oxygen defective and Se-doped p-type BiVO4(001) thin film for the applications of photocatalysis

A C T Monoclinic BiVO 4 is being used as a photocatalyst due to its stability, cost-effectiveness, ease of synthesis, and narrow band gap. Although, the valence band maximum, VBM (-6.80 eV vs vacuum) of BiVO 4 is well below the redox potential of water but having less positive conduction band minimum, CBM (-4.56 eV vs vacuum), responsible for its low efficiency. We have carried out a comprehensive periodic density functional theory (DFT) simulations for the pristine, Oxygen defective (O v ) and Se doped BiVO 4 , to engineer not only its CB edge position but the overall photocatalytic and charge carrier properties. Our theoretical method has nicely reproduced the experimental data of pristine BiVO 4 , which encouraged us to elaborate further its O v and Se-doped characteristics. It is found that both the O v (1% Oxygen vacancy) and Se-doped BiVO 4 (1-2% Se) have ideal band edges, band gaps, and small effective masses of electrons and holes, responsible for high photocatalytic activities. Moreover, Se-doped BiVO 4 behave as p-type semiconductor. Finally, the photocatalytic water-splitting behaviour of the selected surfaces were counterchecked with water interaction, where the strong water adsorption energy of about -38 to -50 kcal/mol, confirms and predicts their higher efficiencies compared to that of parent BiVO 4 .