Synthesis, characterisation, and effective photocatalytic degradation applications in organic dye molecules using CdZnS-loaded UIO-66 composites

Abstract

One of the primary sources of industrial wastewater is dye wastewater, which is challenging for conventional water treatment methods to properly degrade because of its complex composition, high chromaticity, difficulty being biochemically destroyed, etc. The utilization of photocatalysts in conjunction with light energy, or photocatalytic technology, is thought to be a sustainable approach to treating dye wastewater due to its many benefits, including high degradation efficiency, rapid reaction times, and the absence of secondary contamination. We chose to employ CdZnS as a carrier in this research, together with composite UIO-66. The degradation of the dye methylene blue was carried out using the composite CdZnS@UIO-66 as a photocatalyst, and the results were compared to those of pure CdZnS and pure UIO-66. The findings demonstrated that CdZnS@UIO-66 had a noticeably greater photocatalytic efficiency than the other two. Up to 99.87% of the methylene blue in 50 mL of aqueous solution was degraded in the experimental reaction with a catalyst dosage of 0.03 g, pH of 7, and an initial concentration of 30 mg/L of methylene blue aqueous solution when exposed to visible light for 90 minutes. This indicates excellent photocatalytic efficacy in the visible range, the formation of an interfacial electron transfer phenomenon within the heterojunction, and the use of UIO-66 as an electron acceptor to further enhanced photocatalytic effect is caused by the development of interfacial electron transfer phenomena within the heterojunction and UIO-66 as an electron acceptor, which further promotes the internal photogenerated electron-hole separation.