Chen Yi, Li Qian, Su Ruidian, Gao Yixuan, An Ning, Rong Yu, Xu Xing, Ma Defang, Wang Yan, Gao Baoyu
Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266200, PR China.
Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266200, PR China; Shenzhen Research Institute of Shandong University, Shenzhen 518057, PR China.
Water Res. 2025 Aug 15;282:123765. doi: 10.1016/j.watres.2025.123765. Epub 2025 May 2.
As a pre-oxidation unit, developing non-radical pathway-dominant advanced oxidation processes (AOPs) with remarkably-efficient oxidation, superior environmental robustness, and ecological safety is essential in actual water pollution control. Herein, using CoO as an example, we present an oxygen vacancies (OVs)-mediated peracetic acid (PAA) activation process, thereby predominantly generating singlet oxygen (O) for degrading contaminants. In-situ monitoring of PAA activation by OVs-rich CoO (CoO-OVs) reveals that surface oxygen-containing intermediates (e.g., *OH and O) are the precursors of O. Theoretical calculations show that the selective adsorption of terminal oxygen atoms (ATO) in PAA serves as an activity descriptor for O generation. OVs can induce electron redistribution, triggering the ATO-dominated PAA adsorption to form the CoO-OVs-PAA complex, followed by O-O bond breakage to yield *OH. Concurrently, OVs modulate the Co d-band center, lowering the energy barrier for O formation. The system enables ultra-fast catalytic performance (k = 1.17 min) for degrading sulfamethoxazole, outperforming pristine CoO by 11.64-fold. The high-selectivity towards non-radical pathway endows the CoO-OVs/PAA system with remarkable stability in complex environment backgrounds and continuous-flow microreactor. This work not only provides a broad perspective on the modulation of non-radical pathways via defect engineering, but also advances the development of PAA-based AOPs for water decontamination.
作为一种预氧化单元，开发以非自由基途径为主导的高级氧化过程（AOPs），使其具有高效氧化、卓越的环境稳定性和生态安全性，对于实际水污染控制至关重要。在此，以CoO为例，我们提出了一种氧空位（OVs）介导的过氧乙酸（PAA）活化过程，从而主要生成单线态氧（O）来降解污染物。对富含OVs的CoO（CoO-OVs）活化PAA的原位监测表明，表面含氧中间体（如OH和O）是O的前体。理论计算表明，PAA中末端氧原子（ATO）的选择性吸附作为O生成的活性描述符。OVs可诱导电子重新分布，引发以ATO为主导的PAA吸附，形成CoO-OVs-PAA络合物，随后O-O键断裂生成OH。同时，OVs调节Co d带中心，降低O形成的能垒。该系统在降解磺胺甲恶唑方面具有超快的催化性能（k = 1.17 min），比原始CoO性能高出11.64倍。对非自由基途径的高选择性赋予了CoO-OVs/PAA系统在复杂环境背景和连续流微反应器中显著的稳定性。这项工作不仅为通过缺陷工程调节非自由基途径提供了广阔的视角，也推动了基于PAA的AOPs用于水净化的发展。
