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

A series of RGO/La-ZnIn2S4 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 H2 evolution activities have also been evaluated under visible-light irradiation. The H2 production activity of RGO/La-ZnIn2S4 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-ZnIn2S4 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-ZnIn2S4 was discussed in detail.