Bimetallic NiCo₂S₄ Nanorod Cocatalyst Modified the Flower‐Like Zn₃In₂S₆ Microsphere for Visible‐Light‐Driven High‐Efficiency Photocatalytic Hydrogen Production

Abstract

Establishing Schottky barriers is a key tactic for enhancing the separation of photogenerated charge carriers and improving photocatalytic efficiency. Herein, a self‐assembled metal cocatalyst, NiCo2S4 nanorod, is loaded onto the flower‐like Zn3In2S6 microsphere via a hydrothermal method. Under visible light irradiation, the NiCo2S4/Zn3In2S6 composite material achieves a peak H2 production rate of 3436.72 μmol g−1 h−1 within 6 h, marking a 5.4 times greater increase compared to pristine Zn3In2S6. This outperforms the maximum H2 production rate of Pt/Zn3In2S6‐1% within the same 6‐hour timeframe, which is 3323.05 μmol g−1 h−1. Additionally, the apparent quantum efficiency reaches 7.86% at 420 nm. The outstanding photocatalytic activity stems from the synergistic effects between the visible‐light‐active Zn3In2S6 and the conductive cocatalyst NiCo2S4, facilitating spatial electrical promotion. In particular, the formation of a Schottky junction at the interface of NiCo2S4/Zn3In2S6 enables prompt electron transfer to NiCo2S4 nanorods, preventing backflow and thereby promoting the efficient separation of photogenerated charge carriers. Finally, a plausible reaction mechanism is proposed, drawing from the electrochemical characterization results. Thus, this research provides a new approach for designing metal‐semiconductor photocatalysts that are efficient in photocatalytic H2 production through water splitting.