Te modulated heterogeneous remodeling of S atoms in ultrathin ZnInS nanosheets containing S vacancies synergistically enhances CO photoreduction.

Reconfiguration of in situ heterojunction composites without interfacial resistance by substitution of homologous anions for the formation of gradient work function differences inducing the formation of built-in electric field is an effective strategy to enhance the charge separation efficiency. Herein, Te/ZnInS-V (Te/ZIS-V) in situ heterojunction was synthesized by substitution of Te ions for S in ultrathin ZIS containing S vacancies, which can significantly promote photogenerated charge separation, surface electron enrichment, and CO adsorption/activation. The presence of S vacancies and adjacent Te/S double anions, the double active sites constructed by defect engineering promote the desorption of *CO molecules while inhibiting the protonation toward *CHO, which was more favorable for selective CO photoreduction to CO. The experimental results showed that the CO yield of Te/ZIS-V was significantly increased to 672.1 μmol g h compared with pristine ZIS (54.3 μmol g h) and the CO selectivity was close to 83 %. Notably, the life cycle assessment (LCA) of Te/ZnlnS nanosheets with S-vacancy was performed. The evaluation results showed that most of the 17 impact categories showed low overall impact values and were environmentally friendly. Based on the results of this LCA, suggestions were put forward to further optimize the product to reduce carbon emissions.