Spatially Oriented S-Scheme and Schottky Junction in In₂S₃/Ti₃C₂/TiO₂ Ternary Heterojunction for Efficient...

The reasonable structural design and interfacial modification of heterojunction photocatalysts for accelerated charge separation and boosting photocatalytic activity remains a crucial challenge in solar-driven water splitting for H₂ production. Herein, a hierarchical structured In₂S₃/Ti₃C₂/TiO₂ ternary heterojunction was effectively constructed through a facile hydrothermal method integrated with a self-assembly strategy, in which Ti₃C₂ and TiO₂ were loaded on the surface of hierarchical In₂S₃ microspheres assembled from nanosheets. In the photocatalytic system, the in situ electron paramagnetic resonance verifies that the photogenerated charge transfer between In₂S₃ and TiO₂ obeys a typical S-scheme mechanism. Meanwhile, the introduction of Ti₃C₂ MXene as a conductive cocatalyst further promotes the separation and transfer of photogenerated charge through the formation of a Schottky junction, thus remarkably boosting the photocatalytic performance. Under simulated sunlight irradiation, the In₂S₃/Ti₃C₂/TiO₂ ternary heterojunction exhibits a superior H₂ production rate compared to pure TiO₂ and In₂S₃. Moreover, the ternary heterojunction also displays outstanding stability after five consecutive cycling tests. This work highlights the synergistic integration of an S-scheme and Schottky junction in a ternary heterostructure for efficient charge separation, providing a feasible strategy for designing high-performance photocatalysts toward solar-driven H₂ production.