A Fenton-like catalyst was prepared based on isolated Fe single-atom and Fe clusters anchored onto a g-C₃N₄ framework. It exhibited high activity and stability in the heterogeneous activation of peroxymonosulfate (PMS) for tetracycline (TC) degradation. Both experimental and density functional theory calculation results demonstrated that the unique N-coordinated single Fe atom (Fe–N₄) served as active sites with optimal binding energy for PMS activation. The experimental analysis indicated that the single Fe atoms displayed superior catalytic activity to Fe clusters. Furthermore, both high-valent iron-oxo species and single oxygen-dominated nonradical processes caused TC degradation. Among them, single Fe atoms anchored onto Fe-g-C₃N₄ served as Fe–N₄ reactive sites can directly activate PMS to produce high-valent iron-oxo species, which was the key active nonradical species causing TC degradation.

基于孤立的 Fe 单原子和固定在 gC ₃ N ₄骨架上的 Fe 簇制备了类芬顿催化剂。它在过硫酸盐 (PMS) 的异质活化中表现出高活性和稳定性，以降解四环素 (TC)。实验和密度泛函理论计算结果表明，独特的 N 配位单 Fe 原子 (Fe-N ₄ ) 作为活性位点，具有最佳的 PMS 活化结合能。实验分析表明，单个 Fe 原子表现出优于 Fe 簇的催化活性。此外，高价铁氧物种和单一氧主导的非自由基过程都会导致 TC 降解。其中，固定在 Fe-gC ₃ N上的单个 Fe 原子₄作为 Fe-N ₄反应位点可以直接激活 PMS 产生高价铁氧物种，这是导致 TC 降解的关键活性非自由基物种。