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

Abstract

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 μmol H₂ g_cat⁻¹, which is enhanced by 95% compared to that of commercial MoS₂ nanopowder (92.0 μmol H₂ g_cat⁻¹). The possible mechanisms that contribute to the improvement of the visible-light driven photocatalytic performance for the nanocomposite are proposed.