CdS-based Schottky junctions for efficient visible light photocatalytic hydrogen evolution

Heterojunctions photocatalysts play a crucial role in achieving high solar-hydrogen conversion efficiency. In this work, we mainly focus on the charge transfer dynamics and pathways for sulfides-based Schottky junctions in the photocatalytic water splitting process to clarify the mechanism of heterostructures photocatalysis. Sulfides-based Schottky junctions (CdS/CoP and CdS/1T-MoS₂) were successfully constructed for photocatalytic water splitting. Because of the higher work function of CdS than that of CoP and 1T-MoS₂, the direction of the built-in electric field is from CoP or 1T-MoS₂ to semiconductor. Therefore, CoP and 1T-MoS₂ can act as electrons acceptors to accelerate the transfer of photo-generated electron on the surface of CdS, thus improving the charge utilization efficiency. Meanwhile, CoP and 1T-MoS₂ as active sites can also promote the water dissociation and lower the H⁺ reduction overpotential, thus contributing to the excellent photocatalytic hydrogen production activity (23.59 mmol·h⁻¹·g⁻¹ and 1195.8 mol·h⁻¹·g⁻¹ for CdS/CoP and CdS/1T-MoS₂).