0D/2D nanocomposite visible light photocatalyst for highly stable and efficient hydrogen generation via recrystallization of CdS on MoS2 nanosheets. (September 2016) - Ma, Fukun
Abstract: CdS systems represent promising photocatalysts for hydrogen generation; however, these systems are seriously restricted by inherent issues with photocorrosion. Here, the CdS photocorrosion process is prevented and a high stable and effective photocatalyst is obtained in the novel 0D/2D CdS/MoS2 nanosheet composite system. According to crystallization kinetics, the CdS photocorrosion process will be prevented if the S elements resulting from photocorrosion can be reduced back to S 2− in the same photocatalytic system. So a photocorrosion-recrystallization strategy is proposed for the first time to resolve issues with photocorrosion when using CdS photocatalysts. Meanwhile, the recrystallized 0D/2D CdS/MoS2 nanocomposite produces a high quantum efficiency of 23.03% (λex =420 nm), the evolution of hydrogen presents no notable activity losses for up to 400 h. Thus, the approach demonstrated here represents a promising method of designing and fabricating more stable and efficient composite chalcogenide photocatalysts. Graphical abstract: A photocorrosion-recrystallization strategy is proposed to improve photocatalytic performances and resolve issues with photocorrosion for CdS photocatalysts. The obtained CdS/MoS2 nanocomposite shows highly efficient and stable photocatalytic activity for hydrogen generation. Highlights: The photocorrosion of CdS is prevented in the 0D/2D CdS/MoS2 nanosheet system. A photocorrosion-recrystallization strategy is proposed to resolve photocorrosion. The as-obtained nanocomposite shows stable and efficient photocatalytic activity. The recrystallization is verified by the mixtures of CdS with MoS2 or WS2 nanosheets.