Synthesis of AgInS2-xAg2S-yZnS-zIn6S7 (x, y, z = 0, or 1) nanocomposites with composition-dependent activity towards solar hydrogen evolution

Abstract

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.