Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
J Colloid Interface Sci. 2022 Sep 15;622:995-1007. doi: 10.1016/j.jcis.2022.04.179. Epub 2022 May 6.
In view of the increasing threat of overuse of broad-spectrum antibiotics to water environment, here, a series of small molecular intercalated bismuth oxychloride (SBC-X) composite photocatalysts were successfully constructed by a simple stirring synthesis at room temperature. Among them, SBC-0.5 showed excellent photocatalytic performance against the three target broad-spectrum antibiotics in visible light, which was 3.06 times, 5.93 times and 11.64 times higher than that of monomer for degrading tetracycline, norfloxacin and ciprofloxacin, respectively. Through analysis, it was found that the excellent photocatalytic degradation performance of SBC-0.5 was mainly attributed to the greatly improved specific surface area, which increased to 14 times of monomer, providing a large number of reaction sites for the subsequent photocatalytic degradation. Besides, intercalated molecules as charge transfer bridges between nanosheets greatly accelerated the efficiency of photogenerated charge transfer between layers. Free radical trapping experiments and electron spin resonance indicated that superoxide anion radicals played a major role in the photocatalytic degradation, followed by singlet oxygen. Furthermore, nine potential degradation intermediates were identified, and the toxicity was greatly reduced confirmed by ECOSAR software prediction and soybean seed germination and seeding growth experiment. Our work will provide useful information for the purification of wastewater containing antibiotics.
鉴于广谱抗生素过度使用对水环境造成的威胁日益增加，本研究采用室温下简单搅拌合成的方法，成功制备了一系列小分子插层型氧氯化铋（SBC-X）复合光催化剂。其中，SBC-0.5 对三种目标广谱抗生素（四环素、诺氟沙星和环丙沙星）在可见光下具有优异的光催化性能，其降解效率分别是单体的 3.06 倍、5.93 倍和 11.64 倍。通过分析发现，SBC-0.5 具有优异的光催化降解性能，主要归因于其比表面积的大幅提高，达到单体的 14 倍，为后续的光催化降解提供了大量的反应位点。此外，插层分子作为纳米片之间的电荷转移桥梁，极大地加速了层间光生载流子的转移效率。自由基捕获实验和电子顺磁共振表明，超氧阴离子自由基在光催化降解中起主要作用，其次是单线态氧。此外，鉴定了 9 种潜在的降解中间产物，并通过 ECOSAR 软件预测和大豆种子发芽和幼苗生长实验证实其毒性大大降低。我们的工作将为含抗生素废水的净化提供有用的信息。
