MoP@MoO₃ S-scheme heterojunction in situ construction with phosphating MoO₃ for high-efficient photocatalytic hydrogen production

As important artificial photosynthesis, the construction of core-shell heterojunction materials is considered to be one of the effective strategies for designing highly active photocatalysts. Here, the Step-scheme (S-scheme) heterojunction photocatalyst is firmly grown by in situ phosphating. The calcination method uses MoO₃ nanoparticles as the substrate, and the surface of MoO₃ is phosphatized and etched gradually from the outside to the inside using the phosphine gas. The introduced phosphorus atoms can replace MoO₃ oxygen atoms to form Mo-P bonds to generate molybdenum phosphide. The interface interaction dominated by chemical bonds has a stronger interface interaction force, which can promote the interface charge transfer leading to optimizing the MoP@MoO₃ core-shell composite material, adjusting the quality of sodium hypophosphite, and phosphating MoO₃ to varying degrees, producing the best hydrogen production H₂ evolution rate is 10 000.02 μmol h^-1 g^-1. Density functional theory (DFT) calculations and a series of experiments were used to determine the S-scheme charge transfer mechanism in MoP@MoO₃. This design provides a new idea for the introduction of surface-active sites and the construction of mixed anion photocatalysts. At the same time, a new design scheme is provided for the in situ construction of S-scheme interface heterojunction materials.