Oxygen Vacancy-Induced Nonradical Degradation of Organics: Critical Trigger of Oxygen (O2) in the Fe–Co LDH/Peroxymonosulfate System

• DOI: 10.1021/acs.est.1c04600
• Publication Date: 2021-11-05T12:15:26Z
• Authors: Liying Wu; Zhiqiang Sun; Yufei Zhen; Shishu Zhu; Chen Yang; Jing Lu; Yu Tian; Dan Zhong; Jun Ma
• Keywords: Degradation

Ubiquitous oxygen vacancies (Vo) existing in metallic compounds can activate peroxymonosulfate (PMS) for water treatment. However, under environmental conditions, especially oxygenated surroundings, the interactions between Vo and PMS as well organics degradation mechanism are still ambiguous. In this study, we provide a novel insight into activation over Vo-containing Fe–Co layered double hydroxide (LDH). Experimental results show that Vo/PMS is capable of selective via single-electron-transfer nonradical pathway. Moreover, O2 firstly demonstrated most critical trigger system. Mechanistic studies reveal that, with abundant electrons confined vacant electron orbitals Vo, thermodynamically enabled to capture from form O2•– imprinting effect start process. Simultaneously, becomes electron-deficient withdraws sustain electrostatic balance achieve (32% Bisphenol A without PMS). Different conventional activation, collaboration kinetics thermodynamics, endowed ability donate reductant other than an oxidant 1O2. case, 1O2 act indispensable intermediate species accelerate circulation (as high 14.3 mg/L) micro area around promote nano-confinement electron-recycling process 67% improvement degradation. This study provides brand-new perspective natural environments.