Boosting charge transfer and hydrogen evolution performance of CdS nanocrystals hybridized with MoS_2 nanosheets under visible light irradiation

摘要

Cadmium sulfide (CdS) has been currently emerged as a promising class of photocatalyst candidates toward hydrogen evolution from water photosplitting because of its unique electronic structure and favorable optical property. However, pure CdS often suffers from the poor stability and fast charge carrier recombination. Cocatalyst engineering is an effective strategy to activate photocatalytic performance of CdS but remains a challenge. Herein, we develop an effective hydrothermal method to construct microwave-derived CdS nanocrystals hybridized with MoS2 nanosheets. Such hybrids bear the nanocrystal-on-nanosheet heterostructures, ensuring the intimate interfacial contact and increased charge transfer kinetics. The resulting CdS/MoS2 hybrids exhibit highly efficient photoreactivity and excellent photostability for hydrogen evolution under visible light irradiation. The hydrogen generation rate achieved by the optimal CdS/MoS2 is approximately 286 times higher than that of pure CdS. This remarkably boosted performance could be ascribed to synergistically interfacial effect that brings an energy-beneficial driving force to realize the highly efficient transfer, migration, and separation of photoexcited charge carriers.