Elegant Construction of ZnInS/BiVO Hierarchical Heterostructures as Direct Z-Scheme Photocatalysts for Efficient CO Photoreduction.

The ZnInS/BiVO heterostructures were elegantly designed through assembling ZnInS nanosheets onto the surface of BiVO decahedrons. This composite photocatalyst exhibits efficient photocatalytic conversion of CO into CO with a detectable amount of CH in the presence of water vapor. An electron spin-resonance spectroscopy (ESR) technique and density function theory (DFT) calculation affirm the direct Z-scheme structure in ZnInS/BiVO. The larger surface photovoltage (SPV) change and the longer liquid photoluminescence (PL) lifetime of the heterostructure, compared to the individual ZnInS and BiVO components, demonstrate that the Z-scheme structure can effectively promote the recombination of the photogenerated holes in the valence band (VB) of the ZnInS nanosheet with the electrons in the conduction band (CB) of the decahedral BiVO and lead to the abundant electrons surviving in the CB of ZnInS and holes in the VB of BiVO, thus enhancing photocatalytic CO reduction performance. This study may make a potential contribution to the rational construction and deep understanding of the underlying mechanism of direct Z-schemes for advanced photocatalytic activity.