Facile synthesis of a Ag/MoS2 nanocomposite photocatalyst for enhanced visible-light driven hydrogen gas evolution

The current study reports the facile synthesis of a Ag/MoS2 nanocomposite photocatalyst for visible-light driven hydrogen gas evolution. The MoS2 nanoflakes were hydrothermally prepared and then decorated with Ag nanoparticles (NPs) by a simple chemical reduction process at room temperature. Detailed characterizations were carried out to probe the physical structure and properties of the as-synthesized nanocomposite. The nanocomposite shows enhanced visible-light absorption and pronounced quenching of photoluminescence intensity as compared to that of pure MoS2. The photocatalytic hydrogen gas evolution experiments reveal that the Ag NPs can act as an efficient co-catalyst for the MoS2 nanoflakes and subsequently improve the hydrogen gas evolution rate. Ag-loading dependent photocatalytic tests indicate that the 20 wt%-Ag/MoS2 nanocomposite exhibits the highest photocatalytic activity with a hydrogen gas evolution of 179.5 mu mol H-2 g(cat)(-1), which is enhanced by 95% compared to that of commercial MoS2 nanopowder (92.0 mu mol H-2 g(cat)(-1)). The possible mechanisms that contribute to the improvement of the visible-light driven photocatalytic performance for the nanocomposite are proposed.