A dual-functional S-scheme Ti3C2/MoS2–ZnIn2S4 heterojunction for accelerated photocatalytic H2 evolution and efficient solar evaporators

Abstract

The present utilization of photocatalysts in energy conversion fails to meet the increasing demands for enhanced H₂ evolution efficiency and optimal solar energy utilization, primarily due to the rapid recombination of photogenerated carriers at the interface and suboptimal solar utilization rate. This study employs interface engineering of S-heterojunctions to integrate MoS₂–ZnIn₂S₄ onto the surface of the charge transport layer MXene. The high conductivity and layered structure of MXene effectively accelerate charge transfer, reduce electron–hole recombination efficiency, and enhance hydrogen production performance. When this composite material is loaded onto a three-dimensional porous natural silk aerogel (NSA) substrate, it utilizes the photothermal effect of infrared light to simultaneously enhance the generation of hydrogen and water vapor. The photothermal effect of this system exhibits a conversion efficiency of 94.2%, significantly elevating the system temperature and increasing the hydrogen production rate. Under these synergistic effects, the composite material achieves a maximum hydrogen production efficiency of 33.0 mmol g⁻¹ h⁻¹ at room temperature, representing a sixfold improvement compared to MoS₂–ZnIn₂S₄, while the water evaporation rate of Ti₃C₂/MoS₂–ZnIn₂S₄ NSAs reaches 2.6 kg m⁻² h⁻¹. This bifunctional system demonstrates exceptional adaptability and hydrogen production potential, offering a novel solution for solar-driven seawater desalination and hydrogen evolution.