Constructing S-scheme 3D Zn3In2S6/ReS2 heterojunction photocatalyst for simultaneous organic pollutants degradation and hydrogen production

Abstract

Controlling efficient interfacial charge transfer is crucial for developing advanced photocatalysts. This study successfully developed a bifunctional photocatalyst with an S-scheme heterojunction by incorporating ReS 2 into the Zn 3 In 2 S 6 (ZIS) nanoflower structure, enabling the organic pollutants degradation and synergistic hydrogen production. The optimized ZIS/ReS 2 -1% exhibited exceptional photocatalytic efficiency, reaching a 97.7% degradation rate of ibuprofen (IBP) within 2 h, along with a hydrogen generation rate of 1.84 mmol/g/h. The degradation efficiency and hydrogen generation rate were 1.78 and 5.75 times greater than those of Zn 3 In 2 S 6 , respectively. Moreover, ZIS/ReS 2 -1% demonstrated excellent catalytic degradation abilities for various organic pollutants such as ciprofloxacin, amoxicillin, norfloxacin, levofloxacin, ofloxacin, sulfamethoxazole, and tetracycline, while also showing good synergistic hydrogen production efficiency. Electron spin resonance and radical scavenging experiments verified that h + , ·O 2− , and ·OH were the primary reactive species responsible for IBP degradation. The superior photocatalytic performance of the ZIS/ReS 2 -1% was mainly attributed to its broad and intense absorption of visible light, effective separation of charge carriers, and enhanced redox capabilities. The degradation pathway of IBP was unveiled through Fukui function and liquid chromatography-mass spectrometry, and the toxicity of the degradation intermediates was also examined. In-situ XPS and density functional theory (DFT) calculations confirmed the existence of S-scheme heterojunction. This study provided a new pathway for simultaneously achieving organic pollutant treatment and energy conversion. The S-scheme heterojunction constructed from Zn 3 In 2 S 6 and ReS 2 achieves efficient charge carrier separation and enhanced redox capability, thereby facilitating the augmented synergistic effect of ibuprofen degradation and hydrogen generation. • Novel bifunctional ZIS/ReS 2 photocatalyst was successfully constructed. • The formed S-scheme heterojunction promoted efficient charge separation. • ZIS/ReS 2 exhibits enhanced photocatalytic activity for IBP degradation and H 2 generation. • The interface reaction mechanism and IBP degradation pathways were revealed.

Topics & Concepts