Abstract
? 2022 Elsevier B.V.Due to its unique layered structure, tungsten disulfide can be used as an excellent co-catalyst in photocatalytic reactions. In this study, the lamellar WS2 was prepared by the liquid-phase exfoliation method, and the lamellar 2D WS2 has a large specific surface area and many active sites to promote the performance of the photocatalyst.The lamellar WS2 was embedded in CdS nanoparticles by hydrothermal synthesis. Compared with single CdS, the degradation efficiency of the obtained WS2/CdS composite material is 1.8 times higher than that of single CdS under visible light irradiation. Structural characterization shows that the enhanced photocatalytic activity of WS2/CdS composites is closely related to the unique structure of the heterojunction structure between WS2 and CdS that accelerates the transfer of photoexcited electrons. The two-dimensional sheet-like WS2 provides more reaction sites for the CdS attached to it, which improves the absorption of visible light and the migration rate of photogenerated carriers. At the same time, based on first-principles calculations, the charge transfer at the heterojunction interface between WS2 and CdS was obtained. The results show that a unique type II heterojunction is formed after the intercalation of lamellar WS2 in CdS nanoparticles due to the increased band gap of monolayer WS2. This unique structure makes WS2/CdS composite material promising to become a highly efficient multi-purpose photocatalyst.
NSTL
Elsevier