Manganese Cadmium Sulfide Nanoparticles Solid Solution on Cobalt Acid Nickel Nanoflakes: A Robust Photocatalyst for Hydrogen Evolution

Photocatalytic water splitting for hydrogen evolution is one of the most promising methods to mitigate environmental and energy‐related issues. In this study, manganese cadmium sulfide (MnxCd1‐xS) solid solution is used to construct a p–n heterostructure with NiCo2O4 through a hydrothermal method. The Mn0.25Cd0.75S/NiCo2O4 composites are used for photocatalytic hydrogen evolution reaction, and the optimal hydrogen rate with 40 mg of Mn0.25Cd0.75S/NiCo2O4 40 mg (MCS/NCO 40) is 61159 μmol g−1 h−1, which is about 16.3 times than that of pure Mn0.25Cd0.75S. After combining with NiCo2O4, the light absorption scale, the separation efficiency of photogenerated carriers, and the reaction kinetics are enhanced. Moreover, the band offset of MCS/NCO composites is calculated by the core level alignment method, demonstrating the formation of a p–n heterostructure. The built‐in electric field from the p–n heterostructure drives charge transfer and enhances separation efficiency, which results in improved photocatalytic performance. Close to the edge: A Mn0.25Cd0.75S/NiCo2O4 p–n heterostructure is synthesized through a hydrothermal method and shows a high photocatalytic H2 evolution rate of 61159 μmol g−1 h−1. The band edge position is estimated by the core level alignment method, which affords a deeper understanding of the p–n heterostructure.