Novel Ag/CdLa2S4 semiconductor catalysts with enhanced photocatalytic properties

• Ag/CdLa2S4 composites were successfully prepared by a facile process.
• The photocatalytic activity of Ag/CdLa2S4 was higher than that of CdLa2S4.
• 3.18% Ag/CdLa2S4 showed the best photocatalytic activity.
• The activity enhancement mechanism of Ag/CdLa2S4 was discussed.

Novel Ag/CdLa2S4 catalysts with different weight percents of Ag were synthesized by a simple hydrothermal method combined with photo-reduction process, and the obtained Ag/CdLa2S4 composites were characterized by various techniques. The activities of as-prepared samples were evaluated by the photo-degradation of methyl orange (MO) and photocatalytic H2 evolution under visible light (λ>400 nm) irradiation. The results have shown that there is nearly no change in the crystal structure of CdLa2S4 after the loading of Ag nanoparticles, but Ag content in Ag/CdLa2S4 composites played an important role towards the photocatalytic activities of Ag/CdLa2S4 catalysts and 3.18% Ag/CdLa2S4 possessed the best photocatalytic properties. The photo-degradation of MO and hydrogen evolution rate of 3.18% Ag/CdLa2S4 were about 6.7 and 2.0 times than that of pure CdLa2S4, respectively, and the mechanism of activity enhancement was discussed.