Department of Physics and Nanotechnology, SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, Chennai, 603203, India.
Department of Physics and Nanotechnology, SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, Chennai, 603203, India.
Chemosphere. 2022 Jan;287(Pt 4):132380. doi: 10.1016/j.chemosphere.2021.132380. Epub 2021 Sep 29.
Pharmaceutically active compounds are an emerging water contaminant that resists conventional wastewater treatments. Herein, the sonophotocatalytic degradation of Tetracycline (TC) antibiotics as a model contaminant was carried out over a rod-like g-CN/VO (RCN-VO) nanocomposite. RCN-VO nanocomposite was synthesized via ultrasound-assisted thermal polycondensation method. The results showed that the RCN-VO nanocomposite could completely remove the TC in water within 60 min under simultaneous irradiation of visible light and ultrasound. Moreover, the sonophotocatalytic TC degradation (a synergy index of ∼1.5) was superior to the sum of individual sonocatalytic and photocatalytic degradation using RCN-VO nanocomposite. Besides, the enhanced sonophotocatalytic activity of RCN-VO can be attributed to the 1D/2D nanostructure and the S-scheme heterojunction formation between RCN and VO where the electrons migrated from RCN to VO across the RCN-VO interface. Under irradiation, the built-in electric field, band edge bending and Coulomb interaction can synergistically facilitate the unavailing electron-hole pair recombination. Thereby, the cumulative electron in RCN and holes in VO can actively take part in the redox reaction which generates free radicals and attack the TC molecules. This study provides insight into a novel S-Scheme heterojunction photocatalyst for the removal of various refractory contaminants via sonophotocatalytic degradation.
药物活性化合物是一种新兴的水污染物质，它能抵抗传统的废水处理方法。在此，以四环素（TC）抗生素为模型污染物，在棒状 g-CN/VO（RCN-VO）纳米复合材料上进行了超声光催化降解。RCN-VO 纳米复合材料是通过超声辅助热缩聚法合成的。结果表明，在可见光和超声同时辐射下，RCN-VO 纳米复合材料在 60 分钟内就能将水中的 TC 完全去除。此外，超声光催化 TC 降解的协同指数（约为 1.5）优于单独使用 RCN-VO 纳米复合材料的声催化和光催化降解的总和。此外，RCN-VO 的增强超声光催化活性可归因于 RCN 和 VO 之间的 1D/2D 纳米结构和 S 型异质结形成，其中电子从 RCN 迁移到 VO 跨越 RCN-VO 界面。在照射下，内置电场、能带边缘弯曲和库仑相互作用可以协同促进电子-空穴对的复合。因此，RCN 中的累积电子和 VO 中的空穴可以积极参与氧化还原反应，生成自由基并攻击 TC 分子。本研究为通过超声光催化降解去除各种难处理污染物提供了一种新型 S 型异质结光催化剂的思路。
