Rational design and electron transfer kinetics of MoS2/CdS nanodots-on-nanorods for efficient visible-light-driven hydrogen generation

The efficiency of CdS-based photocatalysts for H₂ evolution is limited by the ultrafast charge recombination. Here, we demonstrated the one-pot synthesis of a novel MoS₂/CdS photocatalyst with the structure of partially crystalline MoS₂ nanodots growing on single-crystalline CdS nanorods. This heterostructure not only effectively reduces the bulk and surface charge recombination owing to single-crystalline CdS nanorod matrix and efficient electron transfer, also provides plenty of active sites for hydrogen evolution reaction (HER) and accessible room for prompt hole extraction. The femtosecond transient absorption (TA) analysis reveals the effective electron transfer from CdS to MoS₂ in ~20ps. As a result, MoS₂/CdS exhibits extraordinary photocatalytic activity with a H₂ evolution rate of 60.28mmol/g/h under visible light irradiation, far exceeding all previous HER photocatalysts with MoS₂ as cocatalysts.