Preparation of Au/Tio2/MoS2 plasmonic composite photocatalysts with enhanced photocatalytic hydrogen generation activity

Abstract

Au/TiO2/MoS2 plasmonic composite photocatalysts were synthesized via deposition-precipitation with urea. The photocatalytic activities of the prepared samples were evaluated by performing hydrogen production experiments under Xe lamp irradiation with a 10% (φ, volume fraction) glycerol aqueous solution as the sacrificial agent. The results showed that the optimal content of MoS2 in the Au/TiO2/MoS2 composite is 0.1% (w, mass fraction) and the corresponding H2 production rate was 708.85 μmol·h−1, which was almost 11 times higher than that of TM6.0 with the strongest photocatalytic activity in the all binary TiO2/MoS2 composites. The enhanced photocatalytic activity of the ternary Au/TiO2/MoS2 composites is mainly due to the surface plasmon resonance of the supported Au nanoparticles absorbed on the TiO2/MoS2 layered composite, which show an intense absorption maximum centered around 550–560 nm and induce the photoexcitation of electrons. Meanwhile, the electrons excited by surface plasmon resonance of Au could be injected into the conduction band of TiO2, and they were then transferred to the edges of MoS2 for catalyzing the production of H2.