Bifunctional oxygen-doped graphitic carbon nitride (OCN) was fabricated to activate peroxymonosulfate (PMS) for degrading imidacloprid (IMD). The modulated electronic structure of OCN promoted the adsorption, electron transfer, and formation of the redox site of PMS. The light absorption capacity, and the separation and migration speed of photogenerated carriers of OCN were increased. Consequently, 94.5% of IMD (3.0 mg/L) was removed by OCN-10/PMS process in 2.0 h. Compared with g-C₃N₄/PMS (0.048 h⁻¹), the IMD degradation rate constant of OCN-10/Vis/PMS system (1.501 h⁻¹) was increased by 30.3 times. The PMS oxidation on electron-deficient C atoms and holes, the PMS reduction around electron-rich O atoms and photogenerated electrons, and the multiple reactions of superoxide radical were the sources of the main active species singlet oxygen. Moreover, even under different pH conditions, coexisting anions, humic acid, and other neonicotinoid pesticides, the OCN-10/Vis/PMS system still showed acceptable applicability. Finally, mass spectrometry identified that hydroxylation and N-dealkylation of amines were the primary degradation pathways of IMD. This paper demonstrates an environmental-friendly combined activation strategy of PMS that can be operated day and night with low energy consumption, aiming to pave the way for developing metal-free photocatalysts for high-efficient environmental purification based on advanced oxidation coupling technology.

制备了双功能氧掺杂石墨碳氮化物 (OCN) 以激活过氧单硫酸盐 (PMS) 以降解吡虫啉 (IMD)。OCN 的调制电子结构促进了 PMS 的吸附、电子转移和氧化还原位点的形成。OCN的光吸收能力和光生载流子的分离和迁移速度增加。因此，OCN-10/PMS 工艺在 2.0 小时内去除了 94.5% 的 IMD（3.0 mg/L）。与gC ₃ N ₄ /PMS (0.048 h ^-1 )相比，OCN-10/Vis/PMS体系的IMD降解速率常数(1.501 h ^-1) 增加了 30.3 倍。缺电子C原子和空穴的PMS氧化、富电子O原子和光生电子周围的PMS还原以及超氧自由基的多重反应是主要活性物种单线态氧的来源。此外，即使在不同的 pH 条件下，共存阴离子、腐植酸和其他新烟碱类农药，OCN-10/Vis/PMS 系统仍然显示出可接受的适用性。最后，质谱确定胺的羟基化和N-脱烷基化是IMD的主要降解途径。本文展示了一种环境友好的 PMS 组合激活策略，可昼夜运行且能耗低，