In-situ growth of ZnIn2S4 nanosheets on a Ti-based MOF to form a core-shell heterojunction for enhanced photocatalytic hydrogen evolution
Photocatalytic hydrogen evolution reaction (HER) from pure water is a promising strategy to address critical challenges in energy sustainability and environmental remediation. However, HER over single-component photocatalysts is intrinsically limited by inefficient carrier separation and relatively poor photostability. Forming abundant interfaces between two components is an effective approach for solving these issues. Herein, a series of hierarchical core-shell heterojunction photocatalysts, designated as F@Z-X, was rationally constructed by in situ growing ZnIn2S4 (ZIS) nanosheets on a Ti-based metal-organic framework (FIR-125), demonstrating remarkable structural stability. Due to the abundant intimate contact interfaces and well-matched band structure, the F@Z-X series exhibit enhanced HER performance. Among them, the optimized heterojunction [email protected] shows a photocatalytic hydrogen evolution rate of 3789.45 μmol g−1 h−1, which is about 4.4 and 264.4 times higher than that of pristine ZIS (859.57 μmol g−1 h−1) and FIR-125 (15.32 μmol g−1 h−1), respectively. Moreover, the photocatalyst manifests excellent reusability and durability, maintaining its performance over five consecutive cycles and sixteen hours of continuous reaction. The outstanding performance of [email protected] may be ascribed to an optimal balance among three fundamental photocatalytic processes: sufficient light absorption, exceptional carrier separation, and appropriate surface reaction. This work offers valuable insights into the rational design and controllable synthesis of novel heterojunction photocatalysts for efficient hydrogen evolution.