Synthesis of AgInS2 QDs-MoS2/GO composite with enhanced interfacial charge separation for efficient photocatalytic degradation of tetracycline and CO2 reduction

Abstract

The interfacial regulation strategy between semiconductors can effectively promote the separation efficiency of photogenerated carriers and enhance photocatalytic activity under the synergistic effect. Herein, AgInS2 QDs-MoS2/GO (AIS-MS/GO) composites were prepared by interfacial coupling of AgInS2 QDs (AIS), hierarchical MoS2 and ultrathin GO. Ultrathin GO successfully solved the agglomeration problem of AIS and hierarchical MoS2. Moreover, the photogenerated carriers were effectively separated and transferred under the synergistic effect of the AIS-MS heterojunction and ultrathin GO, thus promoting tetracycline (TC) degradation and CO2 reduction performance. The degradation rate of tetracycline (TC) reached 96.5 %, and the yields of CO and CH4 in the CO2 reduction products reached 52.6 and 28.5 μmol g–1, respectively, when using the optimized photocatalyst. In-situ FTIR analysis indicated that TC is gradually degraded by small molecules on the composite surface, and has excellent dissociation ability of water molecules during the CO2 reduction process. This work provides a new vision for the rational design of heterojunction-based photocatalysts using the interfacial regulation strategy for enhancing interfacial charge separation and photocatalytic performance.