The photocatalytic performance of modified ZnIn2S4 with graphene and La for hydrogen generation under visible light

A series of RGO/La-ZnIn 2 S 4 photocatalysts were successfully synthesized using the hydrothermal method with different amount of RGO (0 wt%, 0.1 wt%, 0.5 wt%, 1.0 wt%, 2.0 wt%, 5.0 wt%) and La (0 wt%, 0.1 wt%, 0.5 wt%, 1.0 wt%, 2.0 wt%, 5.0 wt%) and characterized by various analysis techniques, such as XRD , Raman, SEM, UV–Vis, TEM, BET and PL. The photocatalytic H 2 evolution activities have also been evaluated under visible-light irradiation. The H 2 production activity of RGO/La-ZnIn 2 S 4 was influenced by both La and RGO significantly. The activity reached the best when the amounts of La and RGO were both 1.0 wt%. The hydrogen production rate of 1.0Pt/1.0RGO/1.0La-ZnIn 2 S 4 was 2255 μmol g −1  h −1 and the apparent quantum yield and the energy conversion efficiency were 29.45% and 18.79% at 420 nm respectively. The activity was related to the BET surface area, the pore microstructure and the synergistic effect of RGO and La. On the basis of the characterization of the catalysts, the synergistic effect of RGO and La on the photocatalytic activity of RGO/La-ZnIn 2 S 4 was discussed in detail.