Activation of BiMoO/ZnCdS charge transfer through interface chemical bonds and surface defects for photothermal catalytic CO reduction.

The photocatalytic reduction of CO to high-value fuels has been proposed as a solution to the energy crisis caused by the depletion of energy resources. Despite significant advancements in photocatalytic CO reduction catalyst development, there are still limitations such as poor CO adsorption/activation and low charge transfer efficiency. In this study, we employed a defect-induced heterojunction strategy to construct atomic-level interface Cd-O bonds and form BiMoO/ZnCdS heterojunctions. The sulfur vacancies (V) formed in BiMoO/ZnCdS acted as activation sites for CO adsorption. While the interfacial stability provided by the Cd-O bonds served as an electron transfer channel that facilitated the movement of electrons from the interface to the catalytic site. The V and Cd-O bonds simultaneously influence the distribution of charge, inducing the creation of an interface electric field that facilitates the upward displacement of the center of the d-band. This enhances the adsorption of reaction intermediates. The optimized BiMoO/ZnCdS heterostructure exhibited high selectivity and stability of photoelectrochemical properties for CO, generating 42.97 μmol⋅g⋅h of CO, which was 16.65-fold higher than ZnCdS under visible light drive. This research provides valuable insights for designing photocatalyst interfaces with improved CO adsorption conversion efficiency.