The development of efficient and stable photocatalysts for the degradation of antibiotic pollutants has become a critical challenge in environmental remediation. In this study, a novel n-type heterojunction composite photocatalyst, Ce₀.₉Zr₀.₁O₂/SnIn₄S₈ (CZO/SIS), was successfully synthesized via an in situ precipitation and hydrothermal method. The material exhibited exceptional performance in degrading norfloxacin—a representative fluoroquinolone antibiotic—under visible light irradiation. Comprehensive characterization using SEM, TEM, XRD, XPS, and electrochemical analyses confirmed the formation of a well-defined heterojunction interface between Ce₀.₉Zr₀.₁O₂ and SnIn₄S₈. This structure significantly suppressed the recombination of photogenerated electrons and holes, thereby enhancing both photocatalytic activity and stability, as evidenced by consistent performance over eight consecutive cycles.
The optimized photocatalytic system achieved complete degradation of norfloxacin within 60 minutes and full mineralization within 4 hours, reaching a total organic carbon (TOC) removal efficiency of 99.3 ± 1.7%. LC-QTOF-MS analysis identified eight intermediate compounds during the degradation process, including N1–N8, which were structurally assigned based on retention times and mass spectral data. The degradation pathway involved sequential reactions such as deoxygenation, hydroxylation, carboxylation, and ring cleavage, driven primarily by reactive oxygen species (ROS): photogenerated holes (h⁺), hydroxyl radicals (·OH), and superoxide radicals (·O₂⁻).KRT15 Antibody Formula Free radical scavenger experiments and EPR measurements confirmed that ·O₂⁻ played the dominant role in the degradation mechanism, followed by ·OH and h⁺.EphB2 Antibody Epigenetic Reader Domain
Notably, unlike conventional photolysis, which often leads to toxic byproduct accumulation, the photocatalytic process effectively eliminated norfloxacin without generating hazardous intermediates, making it a sustainable solution for water purification.PMID:35099007 The proposed mechanism involves efficient charge transfer across the n–n heterojunction: photoexcited electrons from SnIn₄S₈ migrate to Ce₀.₉Zr₀.₁O₂, while holes move in the opposite direction, resulting in spatial separation of charges. The accumulated electrons on Ce₀.₉Zr₀.₁O₂ reduce dissolved oxygen to form ·O₂⁻, while holes on Ce₀.₉Zr₀.₁O₂ oxidize OH⁻ or H₂O to produce ·OH, both contributing to the oxidative breakdown of norfloxacin. This synergistic effect significantly enhances redox capability and overall catalytic efficiency.
These findings demonstrate that the Ce₀.₉Zr₀.₁O₂/SnIn₄S₈ composite is a highly promising candidate for the advanced treatment of antibiotic-contaminated wastewater. Its excellent stability, high mineralization capacity, and ability to avoid secondary pollution highlight its potential for practical environmental applications. The work provides valuable insights into the design and application of sulfur-based heterojunction photocatalysts for sustainable water purification technologies.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com
