Chen Mengmeng, Li Mengxue, Li Peng, Lee Stephanie Ling Jie, Tang Juanjuan, Li Qian, Lin Sijie
College of Environmental Science and Engineering, Biomedical Multidisciplinary Innovation Research Institute, Shanghai East Hospital, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, 200092, China.
Environ Sci Pollut Res Int. 2022 Dec;29(60):90768-90778. doi: 10.1007/s11356-022-22000-4. Epub 2022 Jul 25.
The tetracycline (TC) in water has led to serious concern. Graphitic carbon nitride (g-CN) photocatalysts were produced via copolymerization of mono-benzene ring-mediated precursors (urea, melamine, and dicyandiamide) involving salicylic acid (SA) for TC degradation. The SA-modified g-CN samples showed improved visible light absorbance, transfer and separation of photogenerated electrons, and prospective photocatalytic application in TC degradation. As a result, the optimal SA-modified g-CN (2 wt% of SA) using urea (CNU-SA-2) showed 2 times higher TC degradation than that of pristine g-CN. The process of TC degradation was evaluated by the reduction of antibacterial activity and extensively studied by varying the types of TC, initial pH values, co-existing anions, and natural organic materials. In addition, the catalyst could be reused for at least four cycles, indicating good reusability. The main active species were revealed to be h and ·O by scavenging experiments and electron spin resonance. The CNU-SA-2 photocatalyst and TC intermediates during degradation had no adverse impact on zebrafish embryos. This work could provide a design strategy and a perspective on the practical application of g-CN-based photocatalysts for the treatment of wastewater containing antibiotics.
水中的四环素（TC）已引发严重关注。通过单苯环介导的前体（尿素、三聚氰胺和双氰胺）与水杨酸（SA）共聚制备石墨相氮化碳（g-CN）光催化剂用于TC降解。SA改性的g-CN样品表现出改善的可见光吸收、光生电子的转移和分离，以及在TC降解方面有前景的光催化应用。结果，使用尿素的最佳SA改性g-CN（SA含量为2 wt%）（CNU-SA-2）的TC降解率比原始g-CN高2倍。通过抗菌活性的降低来评估TC降解过程，并通过改变TC类型、初始pH值、共存阴离子和天然有机物质进行了广泛研究。此外，该催化剂可重复使用至少四个循环，表明具有良好的可重复使用性。通过清除实验和电子自旋共振揭示主要活性物种为h和·O。降解过程中的CNU-SA-2光催化剂和TC中间体对斑马鱼胚胎没有不利影响。这项工作可为基于g-CN的光催化剂处理含抗生素废水的实际应用提供设计策略和前景。
