Peroxymonosulfate (PMS)-based advanced oxidation process (AOP) has attracted great attention as an effective technique for oxidatively decomposing organic pollutants. The PMS activation mechanisms, nevertheless, are still ambiguous in many cases, and, thus, controlling PMS activation pathways for efficient pollutant removal remains challenging. In this work, taking defective PrBa_0.5Sr_0.5Co_1.5Fe_0.5O_5+δ (PBSCF) as a model system, we demonstrate that oxygen vacancies (V_o^••) strongly promote PMS-based AOP, and PMS activation pathways are effectively tuned. Excessive V_o^••s are found to modify the surface charge distribution, change PMS adsorption configuration, and break the S–O bond of PMS. As a result, the radical process is promoted, and the predominant nonradical activation pathway shifts from an electron transfer process to singlet oxygen formation. Our mechanistic understanding can guide the rational design of catalysts for efficient water remediation.

基于过氧单硫酸盐 (PMS) 的高级氧化工艺 (AOP) 作为氧化分解有机污染物的有效技术而备受关注。然而，PMS 激活机制在许多情况下仍然不明确，因此，控制 PMS 激活途径以有效去除污染物仍然具有挑战性。在这项工作中，以有缺陷的 PrBa _0.5 Sr _0.5 Co _1.5 Fe _0.5 O _5+δ (PBSCF) 作为模型系统，我们证明氧空位 ( V _o ^•• ) 强烈促进基于 PMS 的 AOP，并且 PMS 激活途径是有效的调谐。V _o过大^••发现 s 可以改变表面电荷分布，改变 PMS 吸附构型，并破坏 PMS 的 S-O 键。结果，自由基过程得到促进，主要的非自由基活化途径从电子转移过程转变为单线态氧形成。我们对机理的理解可以指导催化剂的合理设计，以实现有效的水修复。