A Facet-Dependent Schottky-Junction Electron Shuttle in a BiVO4{010}-Au-Cu2O Z-Scheme Photocatalyst for Efficient Charge Separation

Interfacial charge separation and transfer are the main challenges of efficient semiconductor-based Z-scheme photocatalytic systems. Here, it is discovered that a Schottky junction at the interface between the BiVO4 {010} facet and Au is an efficient electron-transfer route useful for constructing a high-performance BiVO4{010}-Au-Cu2O Z-scheme photocatalyst. Spectroscopic and computational studies reveal that hot electrons in BiVO4 {010} more easily cross the Schottky barrier to expedite the migration from BiVO4 {010} to Au and are subsequently captured by the excited holes in Cu2O. This crystal-facet-dependent electron shuttle allows the long-lived holes and electrons to stay in the valence band of BiVO4 and conduction band of Cu2O, respectively, contributing to improved light-driven CO2 reduction. This unique semiconductor crystal-facet sandwich structure will provide an innovative strategy for rational design of advanced Z-scheme photocatalysts.