Visible light-induced hole transfer in single-nanoplate Cu 1.81 S-CdS heterostructures.

The separation and transfer of photogenerated carriers in semiconducting materials are essential processes that determine the efficiency of optoelectronic devices and photocatalysts, and transient absorption spectroscopy provides a powerful support for exploring the diffusion and recombination of photogenerated electrons and holes. Herein, high-quality Cu 1.81 S nanoplates were synthesized by a hot injection method, and were used as starting templates for the preparation of Cu 1.81 S-CdS heterojunctions and CdS nanoplates by cation exchange. Their carrier dynamics were investigated by transient absorption spectroscopy, which revealed that photogenerated holes may be transferred from the CdS phase to the Cu 1.81 S phase under 400 nm excitation. This process is in the opposite direction to the hole transfer induced by near-infrared localized surface plasmon resonance in copper sulfide heterostructures. Moreover, density functional theory calculations were used to further explain the visible light-induced hole transport process. This transfer is a potential way to increase the rate of H 2 production and enhance the photostability of the catalyst.