Supramolecular Electrostatic-Driven Construction of ZnIn₂S₄/NiTCPP Heterojunctions for Efficient Photocatalytic...

Solar-driven photocatalytic water splitting for hydrogen production is a highly promising clean energy technology, yet its practical application is constrained by issues such as narrow light absorption, severe carrier recombination, and sluggish surface reaction kinetics. This paper proposes a supramolecular electrostatic self-assembly strategy to construct a nickel porphyrin (NiTCPP)-modified Z-scheme ZnIn₂S₄ heterojunction photocatalyst (denoted Ni-ZIS-10). This design facilitates the formation of a compact interface through the directional interaction between carboxyl groups and surface hydroxyl groups, which not only extends the light response range into the near-infrared (NIR) region but also achieves efficient separation and migration of photogenerated carriers driven by the Z-scheme band structure and the built-in electric field. Under visible-light irradiation, Ni-ZIS-10 exhibits a hydrogen evolution rate (HER) that is more than 7-fold higher than that of pristine ZnIn₂S₄, alongside good cyclic stability. Mechanistic studies reveal that the nickel active center plays a pivotal role in promoting interfacial charge transfer and accelerating the proton reduction process with its performance outperforming metalloporphyrin control systems based on copper and zinc. This research provides insights into interface design strategies for constructing efficient and stable non-noble-metal Z-scheme photocatalytic systems.