CdS-sensitized K2La2Ti3O10 composite: A new photocatalyst for hydrogen evolution under visible light irradiation

A series of cadmium sulfide (CdS)-sensitized layered perovskite-type compound (K2La2Ti3O10) composites (hereafter designated as CdS/K2La2Ti3O10) photocatalysts were synthesized by loading CdS particles on K2La2Ti3O10 via a facile precipitation method. The photocatalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and ultraviolet–visible (UV–vis) diffuse reflection spectra. The photocatalytic activities of these catalysts for H2 production were investigated in the presence of a Na2S sacrificial reagent under visible light irradiation. The results revealed that the CdS/K2La2Ti3O10 samples displayed a strong light absorption in the visible region, and the UV–vis diffuse reflectance spectra changed with the proportion of CdS present. The composite photocatalysts exhibited enhanced photocatalytic hydrogen evolution, and the highest activity of 50.53 μmol was achieved using 5 wt.% CdS/K2La2Ti3O10. This enhanced photocatalytic activity can be attributed to the efficient separation of electron–hole pairs and prevention of their recombination under the joint effects of the electric field established at the heterojunction and the layered space of K2La2Ti3O10.

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► CdS was deposited on the surface of K2La2Ti3O10 via a precipitation method.
► the deposition of CdS greatly increased the visible light absorption for K2La2Ti3O10.
► The composite photocatalysts exhibited significant enhancement in photocatalytic hydrogen evolution.