In Situ Derivatization of NiAl-LDH/NiS a p–n Heterojunction for Efficient Photocatalytic Hydrogen Evolution

Owing to the creation of a large number of surface active sites, surface modification is an efficient strategy for improving the catalytic performances of photocatalysts. Herein, zero-dimensional (0D) p-type NiS species were developed in situ on the large surface of NiAl-LDH by controlled vulcanization. Importantly, the development of the 0D p-type NiS species not only enriched the active sites but also triggered the in situ formation of a NiS/NiAl-LDH p–n heterojunction due to NiAl-LDH, which was utterly underdeveloped in the vulcanization modification procedure. This undoubtedly accelerated the faster separation and migration of charge carriers and yielded improved photocatalytic hydrogen evolution. The optimum hydrogen production rate of the NiS/NiAl-LDH photocatalyst could reach 3408 μmol·g–1·h–1 using a 5 W LED simulation visible light, which was 52-fold that of NiAl-LDH. The design and construction of the in situ p–n heterojunction may provide a perspective for the formation of p–n heterojunction photocatalysts with a closer contact interface and highly enhanced photocatalytic activity.