MnCdS Cluster Particles Composited with NiTiO₃ Nanoparticles for Efficient Photocatalytic Hydrogen Production

In photocatalysis, single catalyts often face issues such as low photogenerated carrier separation efficiency, high carrier migration resistance, and catalyst system instability, which result in low photocatalytic hydrogen production efficiency. To overcome these challenges, researchers commonly employ cocatalysts. In this study, MnCdS was coupled as the main catalyst with NiTiO 3 as the secondary catalyst to adjust the migration trajectory of photogenerated carriers and inhibit their recombination. This study investigates, through experimental analysis, the mechanism by which introducing the cocatalyst NiTiO 3 improves the yield of hydrogen evolution catalyzed by MnCdS during light irradiation. The final experimental outcomes demonstrate that NiTiO 3 nanoparticles were successfully anchored onto the surface of MnCdS clusters via surface modification, resulting in the formation of a type II–II heterojunction at the interface between the two materials. The establishment of this type II–II heterojunction induced the directional migration of photogenerated charge carriers to distinct regions within the interface. This divergence in migration paths facilitated the spatial separation of photogenerated electrons and holes, effectively mitigating their recombination within the same catalytic system, and ultimately enhancing the hydrogen evolution efficiency.