In　this　study,　based　on　the　extensive　discussion　of　the　phase　transformation　process　of　metal-organic　frameworks　(MOFs)——MIL-88A(Fe)　under　thermal　treatment,　the　catalytic　performance　of　MIL-88A-derived　iron/carbon　(FexC)　composites　on　persulfate　(PS)　activation　for　phenol　degradation　was　investigated.　FexC-600　(γ-Fe2O3/C)　exhibited　a　superior　catalytic　activity　on　PS　activation　for　phenol　degradation　due　to　higher　carbon　content,　more　sp2-hybridized　structure,　carbonyl　group　and　defective　sites　in　composites,　in　which　98.23%　of　phenol　(20　mg/L)　was　degraded　after　60　min　with　0.3　g/L　catalyst　and　0.3　g/L　PS　at　ambient　pH　(6.1).　The　phenol　degradation　experiments　and　mechanism　studies　revealed　that　there　was　a　catalytic　synergism　between　iron　oxides　and　carbon　component　in　FexC　400-600　composites.　Moreover,　sulfate　radicals　(SO4[rad]−),　hydroxyl　radical　(•OH),　singlet　oxygen　(1O2)　and　interfacial　electron　transfer　process　all　involved　in　the　degradation　of　phenol　by　FexC　400-600　composites,　but　the　1O2-mediated　non-radical　oxidation　was　the　dominant　pathway　rather　than　reactive　radicals.　Finally,　the　possible　mechanism　of　PS　activation　on　FexC　400-600　composites　was　proposed.　This　work　discusses　the　synergistic　catalytic　mechanism　of　FexC　composites　on　PS　activation,　and　favors　to　provide　a　better　understanding　of　the　metal　species　and　carbon　component　interaction　in　iron/carbon-based　materials.　©　2020　Elsevier　B.V.