Metal sulfides-based nanomaterials have been used as a class of efficient solar driven photocatalysts. However, the H₂-production rate observed over these photocatalysts remains problematic. Here, the AgInS₂-xAg₂S-yZnS-zIn₆S₇ (x, y, z = 0 or 1) nanocomposites with controlled compositions have been successfully prepared by a simple hydrothermal method with AgI polyhedrons as silver source. The obtained AgInS₂-xAg₂S-yZnS-zIn₆S₇ nanocomposites showed a composition-dependent activity for H₂ evolution from aqueous solution under simulated sun-light irradiation. The results showed that the optimized product of AgInS₂-Ag₂S-ZnS nanoparticles synthesized with the precursor ratio of Ag:Zn = 1:1 exhibited the highest H₂ evolution rate of 5.4 mmol·g-1·h-1. Furthermore, the catalyst can be used for 20 h without loss of activity, showing its high stability. It opens a new path to achieve highly efficient solar photocatalyst for H₂ evolution from water splitting.
Keywords: AgInS2-xAg2S-yZnS-zIn6S7; H2 evolution; heterojunction; photocatalysis.