Emb e dding laser-generate d CdTe nanocrystals into ultrathin ZnIn 2 S 4 nanosheets with sulfur vacancies for boosted photocatalytic H 2 evolution

To suppress the inner charge recombination and inject vast electrons, CdTe nanocrystals are embedded into ultrathin ZnIn2S4 nanosheets to construct ZnIn2S4/CdTe heterostructures, where the nanocrystals are generated by a laser irradiation method. The optimal ZnIn2S4/CdTe heterojunction exhibits an excellent catalytic activity of 24.3 mmol/h/g, which is relatively high among the ZnIn2S4-based photocatalysts with-out noble metals. This enhancement is ascribed to a win-win mechanism of nanoscale heterojunctions and sulfur vacancies. The strong electron coupling effect, which is verified by density functional the-ory (DFT) calculations, impels the photo-generated electrons transfer from CdTe to ZnIn2S4, boosting the charge separation. Meanwhile, the sulfur vacancies existing in ZnIn2S4 can capture photoelectrons and act as active sites, facilitating the H 2 generation reaction. In addition, the ZnIn2S4 base and the ZnIn2S4/CdTe heterojunction also possess an evident photothermal effect and renewable cycle phenomena, enhancing the photocatalytic performance. This research provides new insights into the regulation of charge transfer through embedding nanocrystals.& COPY; 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.