Understanding the origin of high activity of graphene layers encapsulated Fe-N-C catalysts in Fenton-like reaction is critical, but still challenging for developing catalysts with high activity and durability. Therefore, we prepared a highly active Fe-N-C catalyst (Fe_xMn_y-Fe@NCs) containing FeN₄ coordination to activate peroxymonosulfate (PMS) toward 4-aminobenzoic acid ethyl ester (ABEE) degradation, and revealed the multiple catalytic reaction sites by investigating the composition and the structure of the catalyst. The relationship between the catalytic degradation performance and multiple catalytic reaction sites was performed on the basis of both experiments and density functional theory (DFT) calculations. The catalytic performance of Fe₂Mn₁-Fe@NCs was found to show optimal catalytic degradation performance. Pyrrolic N served as adsorption site as well as singlet oxygen generation site to promote the catalytic degradation. Fe-pyridinic N-C acted as hydroxyl radical and sulfate radical generation site. Both singlet oxygen and superoxide radical were dominated the catalytic reaction. The insight achieved from this study may be further applied to other Fe-N-C catalysts design and further efficient organic pollution remediation.

了解类Fenton反应中石墨烯层包裹的Fe-NC催化剂的高活性来源至关重要，但对于开发具有高活性和耐久性的催化剂仍然具有挑战性。因此，我们制备了高活性的Fe-NC催化剂（Fe _x Mn _y -Fe @ NCs），其中包含FeN ₄配位以激活过氧单硫酸盐（PMS）向4-氨基苯甲酸乙酯（ABEE）降解，并揭示了多个催化反应位点通过研究催化剂的组成和结构。在实验和密度泛函理论（DFT）计算的基础上，进行了催化降解性能与多个催化反应位点之间的关系。Fe ₂的催化性能发现Mn ₁ -Fe @ NCs具有最佳的催化降解性能。吡咯N用作吸附位以及单线态氧生成位，以促进催化降解。Fe-吡啶基NC充当羟基自由基和硫酸根自由基的生成位点。单线态氧和超氧自由基均主导催化反应。从这项研究中获得的见识可以进一步应用于其他Fe-NC催化剂设计和进一步有效的有机污染修复。