ZnCdS/NiAl hydrotalcite S-scheme heterojunction for efficient photocatalytic hydrogen evolution

ZnCdS/NiAl hydrotalcite S-scheme heterojunction with highly effective photocatalytic hydrogen evolution activity was devised and prepared by a simple solution-based mixing way. Layered double hydroxide (LDH), also called hydrotalcite-like compound, is composed of adjustable metal cations and exchangeable anions between layers. The hydrogen evolution performance of ZnCdS/NiAl LDH is about 7 times that of ZnCdS and 130 times that of NiAl LDH. Because the rod-shaped ZnCdS and the layered NiAl LDH can construct close interface contact. This interface contact helps to accelerate charge transfer, thereby achieving more effective photocatalytic hydrogen evolution. The S-scheme ZnCdS/NiAl LDH heterojunction catalyst shows excellent hydrogen evolution and good stability, which not only gets benefits from the prominent performances of the cob-like ZnCdS and the layered NiAl LDH but also the matching bandgap structure for them. The configuration of the S-scheme ZnCdS/NiAl LDH heterojunction catalyst accelerates the rapid charge movement and inhibits the recombination of charge carriers, thereby greatly enhancing visible-light-driven water splitting, which is corroborated by the PL spectrum, I-T, LSV, EIS, MottSchottky and UV–vis DRS studies, etc.