控制合成单原子修饰3DMXenes/FeOx多级中空微球光类芬顿去除PPCPs的研究

PPCPs涵盖了众多结构复杂、差异性大的污染物，其来源与人类的日常生活密切相关，具有不可或缺性。目前应用于城市污水处理系统中的常规处理工艺无法将这类污染物有效去除。近期发展起来的PMS高级氧化技术被认为是传统芬顿工艺的理想替代者，然而催化剂氧化还原循环缓慢严重制约了PMS的活化效率。我们的前期研究表明光催化耦合PMS构成的协同体系可以促进催化剂表面离子的氧化还原循环过程，但所用的体相催化剂的原子利用率不高。本项目拟研究单原子催化剂在光类芬顿体系中的应用，制备出单原子修饰的3DMXenes/FeOx多级中空微球，研究其在光照下对PMS的活化机制，探究单原子负载量和分散度以及特殊的多级中空结构对催化反应的影响，探究自由基链式反应途径以及PPCPs的降解历程，揭示单原子催化剂在光类芬顿体系中降解PPCPs的机理。研究结果为废水中PPCPs的单原子光类芬顿催化氧化去除提供了理论指导。

PPCPs includes a large number of pollutants with complex structure and great differences, whose sources are closely related to human daily life and indispensable. At present, the conventional treatment process used in urban sewage treatment system can not effectively remove this kind of pollutants. Recently, peroxymonosulfate (PMS)-based Advanced Oxidation Processes (AOPs) is considered to be an ideal alternative to traditional Fenton process. However, the slow redox cycle of catalyst seriously restricts the activation efficiency of PMS. Our previous study showed that the synergistic effect of photocatalysis coupled with PMS could promote the redox cycle of ions on the catalyst surface, but the bulk catalysts was incapability to fully utilize all of the metal atoms. This project intends to study the development and design of single-atom catalysts in the photo-Fenton-like system, and research the activation mechanism of PMS under light using the as-prepared single-atom modified 3D MXenes/FeOx hierarchical hollow microspheres, explore the influence of single-atom loading and dispersion, as well as the distinctive hierarchical hollow structure on the catalytic activity, study the chain reaction pathways of free radical and the degradation process of PPCPs, and illustrate the degradation mechanism of PPCPs in photo-Fenton-like system. The results provide theoretical guidance for the single-atom photo-Fenton-like catalytic oxidation of PPCPs in wastewater.