Hydrothermal synthesis of ZnS on monolayer MXene(Ti 3 C 2 T x ) for degradation of organics under natural light

ZnS is a well-known photocatalyst in the field of water treatment, but its applicability is limited due to poor visible light sensitivity, low photon efficiency, and photo corrosion. In this study, a new type of ZnS/Ti3C2Tx composite photocatalyst was developed by growing ZnS microspheres on a single-layer Ti3C2Tx, which is based on the sheet-like structure and metal-like characteristics of Ti3C2Tx. The resulting Ti3C2Tx-based composite photocatalyst with ZT0.35% showed superior catalytic activity in the degradation of methyl orange under natural light. The catalytic rate constant was 3.51 times higher than that of ZnS alone, reaching a maximum of 0.0244 min−1. Within 120 minutes, the degradation rate of methyl orange was 96.3%, while that of ZnS was only 41.6%. Photoluminescence and free radical scavenging experiments revealed that the composite structure is responsible for the improved photocatalytic activity and that the ZnS/Ti3C2Tx structure is favorable for the separation and transport of photogenerated carriers. The developed ZnS/Ti3C2Tx composite has great potential as a photocatalyst for the degradation of organic contaminants.