Iron　and　nitrogen　co-doped　carbon-based　catalysts　have　garnered　significant　attention　for　their　efficacy　in　the　degradation　of　Rhodamine　B　(RhB),　Tetracycline　(TC)　and　other　organic　pollutants　through　peroxymonosulfate　(PMS)　activation.　However,　designing　catalysts　with　both　high　activity　and　abundant　active　sites　has　proven　challenging,　primarily　due　to　the　limited　understanding　of　the　structure-activity　relationship.　Herein,　we　present　a　straightforward　synthesis　of　iron　and　nitrogen　co-doped　carbon　nanosheets　(FeNC)　that　exhibit　exceptional　activity　in　activating　PMS　for　degradation　of　RhB　and　TC.　The　FeNC　material　shows　robust　resistance　to　interference　across　a　wide　pH　of　1.5　to　10,　resistance　to　inorganic　anions　and　humic　acid　(HA).　More　importantly,　the　Fe3C　nanoparticles　are　uniformly　anchored　within　the　carbon　layer,　effectively　prevent　metal　leaching.　Unlike　the　traditional　sulfate　radical-based　advanced　oxidation　processes,　our　study　reveals　that　non-radical　singlet　oxygen　(1O2)　serves　as　the　main　reactive　oxygen　species　(ROS)　responsible　for　the　degradation　processes　through　quenching　tests　and　electron　paramagnetic　resonance　(EPR)　analysis.　Structural　characterizations　and　spectroscopic　study　indicate　that　the　potential　active　sites　on　FeNC,　namely　C[dbnd]O,　graphitic　and　pyridinic　nitrogen　play　an　important　role　in　this　degradation.　Particularly　noteworthy　is　the　discovery　that　Fe3C　species,　present　in　the　FeNC-900/PMS　system,　also　contribute　significantly　to　the　degradation　of　TC.　Moreover,　we　have　proposed　potential　degradation　pathways　for　RhB　and　TC　based　on　the　results　of　liquid　chromatograph　mass　spectrometer　(LC-MS)　measurement.　Overall,　this　study　offers　novel　insights　into　the　development　of　heterogeneous　iron　and　nitrogen　co-doped　carbon-based　catalysts　for　advanced　oxidation　processes　(AOPs)　via　PMS　activation.　©　2024　Elsevier　B.V.