Herein, ternary metal-organic frameworks (MOFs)-derived MnCoFeO with different levels of oxygen vacancies (O_v) were designed by adjusting the doping amount of Mn and employed to activate peroxymonosulfate (PMS) for sulfamethoxazole (SMX) degradation. The MnCoFeO-2 with the largest O_v content exhibited the highest SMX degradation efficacy. Almost 100% of SMX was removed within 5 min using the MnCoFeO-2/PMS system. The reaction rate constant (k_obs) was 1.7321 min⁻¹, which was 4.1 times that of CoFeO (0.4195 min⁻¹). Both the SO₄^•− and ¹O₂ were the dominant reactive oxygen species. Significantly, the relationship among O_v, radical pathways, and non-radical pathways was explored for the first time. The results showed that O_v could regulate the radical pathways by promoting the adsorption of PMS onto MnCoFeO-2. O_v was positively correlated with ¹O₂ (P < 0.05) and facilitated the direct electron transfer. The superior catalytic activity of MnCoFeO was attributed to the Fe, Co, Mn active sites, Lewis basic sites and O_v in MnCoFeO. Mn(II) not only contributed to the formation of O_v, but also facilitated the reduction of Fe(III). Additionally, O_v was mainly concentrated near the low-valent metal ions, thus the synergistic effect between the metal active sites and O_v promoted the activation of PMS.

在此，通过调整Mn的掺杂量设计了具有不同氧空位（O _v）水平的三元金属有机骨架（MOFs）衍生的MnCoFeO，并用于活化过氧单硫酸盐（PMS）以降解磺胺甲恶唑（SMX）。_{具有最大 O v}含量的 MnCoFeO-2表现出最高的 SMX 降解效率。使用 MnCoFeO-2/PMS 系统在 5 分钟内去除了几乎 100% 的 SMX。反应速率常数（k _obs）为1.7321 min ^-1，是CoFeO（0.4195 min ^-1）的4.1倍。SO ₄ ^•−和¹ O ₂是主要的活性氧。值得注意的是，首次探索了Ov、自由基途径和非自由基途径_之间的关系。结果表明，O _v可以通过促进 PMS 在 MnCoFeO-2 上的吸附来调节自由基途径。O _v与¹ O ₂呈正相关（P < 0.05）并促进了直接电子转移。MnCoFeO优异的催化活性归因于MnCoFeO中的Fe、Co、Mn活性位点、Lewis碱性位点和O _v。Mn(II)不仅促进了O _v的形成，还促进了Fe(III)的还原。此外，O _v主要集中在低价金属离子附近，因此金属活性位点与O _v的协同作用促进了PMS的活化。