Regulating the thickness of the NiO layer to optimize the photoinduced carrier separation behavior of BiVO4

Abstract

The rational and effective regulation of interfacial charge separation and transport through the construction of composites is an effective strategy to improve photocatalytic performance. Here, we prepared NiO/BiVO₄ layered nanostructured composite films on yttrium stabilized zirconia (001) substrates with ITO as a conductive buffer layer by magnetron sputtering. The NiO layer serves as an optimization layer to modulate the charge separation efficiency of BiVO₄ by varying its thickness. The photocatalytic synthesis of H₂O₂ under 440 nm monochromatic light irradiation at 3 min of NiO deposition showed a 1.6-fold improvement in performance compared with pure BiVO₄. The type-II band structure formed by NiO and BiVO₄ facilitates the effective separation of electron and hole pairs, achieving the transfer of holes from BiVO₄ to the NiO layer and improving the photocatalytic efficiency of H₂O oxidation.