CdS Nanorods Coupled with WS₂ Nanosheets for Enhanced Photocatalytic Hydrogen Evolution Activity

Abstract

WS2 nanosheets–CdS nanorods with heterojunctions were prepared by an ultrasonic/exfoliation method using dimethylformamide as the dispersing agent. CdS nanorods were coupled with small WS2 nanosheets as a result of exfoliation. An excellent hydrogen production rate of 1222 μmol h–1 (20 mg of catalyst) was achieved over the WS2–CdS composite with a WS2-to-CdS mass ratio of 1.6:1 under visible-light irradiation (λ ≥ 400 nm). The efficient evolution of hydrogen is attributed to promotion of the separation of photogenerated charge carriers due to the presence of heterojunctions created on the surface.