Promoting the photocatalytic H_2 evolution activity of CdLa_2S_4 nanocrystalline using few-layered WS_2 nanosheet as a co-catalyst

摘要

In this work, a series of few-layered WS2 nanosheets were fabricated through an ultrasonic stripping method assisted by a hydrothermal process, then the WS2/CdLa2S4 composites were prepared by growing CdLa2S4 nanocrystallines in situ on the surface of few-layered WS2 nanosheets through an ultrasonic stripping method followed by a hydrothermal process. Investigation shows that the prepared WS2/CdLa2S4 composite shows an excellent photocatalytic activity toward hydrogen evolution from water with visible light response. The optimized content of few-layer of WS2 nanosheet was estimated to be around 5 wt of CdLa2S4 nanocrystalline and the corresponding hydrogen evolution rate is about 6 times higher than that of single phase of CdLa2S4 nanocrystalline. Furthermore, the WS2/CdLa2S4 composites still keep high photocatalytic activity after 4 times circles. Combining few- layered WS2 nanosheets as a co-catalyst with CdLa2S4 nanocrystallines not only facilitate the efficient separation of photogenerated carriers, but also promote more active sites for hydrogen evolution. Considering its excellent photocatalytic activity toward H-2 evolution with visible light response and photochemistry stability, the obtained WS2/CaLa2S4 composite photocatalyst has promising application for practical photocatalytic H-2 production from H2O drived by solar energy. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.