Band alignment and photocatalytic activity of monoclinic BiVO4 (010) and (100) films with SrTiO3

The calculated valence band and conduction band offsets of a- and b-oriented BVO with STO showed the positions of conduction band and valence band for (010) facet are 0.23 eV higher than that for (100). [Display omitted] •The a- and b-oriented BiVO4 films were successfully fabricated on STO (100) and YSZ (001) substrates, respectively.•The (010) and (100) facets of BiVO4 form interfaces with SrTiO3 for evaluating the band positions.•The band edge positions of BiVO4 varied with the orientation.•BiVO4 exposed the (100) facet has better photocatalytic performance than (010). The crystal plane with the highest electron and hole mobility in a material is very important to physical and chemical properties. Herein, the BiVO4 (BVO) thin films exposed (010) or (100) planes which pointed out as the facets with the highest electron and hole mobility, and formed the interface with SrTiO3 (STO) were fabricated by magnetron sputtering. The band edge offsets calculation results of oriented BVO and STO show that the conduction band and valence band positions of the BVO (010) plane are 0.23 eV higher than those of (100). The average generation rates of H2O2 in BVO(100) are 5.3 × 10−2 and 3.8 × 10−1 µmol h−1 under 440 nm monochromatic light and full arc Xe lamp irradiation, which are 1.8 and 1.6 times higher than those in BVO(010), respectively.