Enhanced interfacial charge transfer by oxygen vacancies in ZnCdS/NiCo-LDH heterojunction for efficient H2 evolution

The elaborate modulation of charge transfer in Z-scheme heterojunctions is of significant importance yet poses a formidable challenge for achieving efficient photocatalytic hydrogen production. The present study reports the fabrication of ZnCdS nanoparticle wrapped by NiCo-layered double hydroxide with enriched oxygen vacancies (ZCS@LDH-Ov) was fabricated, which exhibits enhanced interfacial binding and internal electric field (IEF) in comparison to ZCS@LDH. Under visible-light irradiation, the as-prepared ZCS@LDH-Ov exhibits a superior photocatalytic H2 production rate of up to 2.68 mmol·g−1·h−1, which is approximately 9.24-fold and 2.68-fold of the pristine ZnCdS and ZCS@LDH, respectively. The stability of the photocatalyst after 5 cycles is obviously enhanced, with ZCS@LDH exhibiting a remaining hydrogen evolution reaction (HER) rate of 52.7 % and ZCS@LDH-Ov demonstrating an impressive remaining rate of 98.2 %. The Z-scheme facilitates rapid charge transfer and efficient separation, thereby enhancing the catalytic activity for HER. The excellent recyclability of ZCS@LDH-Ov is primarily attributed to enhanced photo-corrosion resistance of ZnCdS, which can be ascribed to the efficient transfer of photo-generated holes through a rapid interfacial charge pathway.