Doping　polymetals　on　Fe-based　catalysts　is　proved　to　be　an　effective　way　to　improve　the　performance　on　activating　persulfate.　In　this　paper,　a　highly　efficient　persulfate　activation　catalyst　(FeCo@MoS2)　was　successfully　synthesized　by　introducing　MoS2　onto　the　surface　of　FeCo　nanoboxes.　During　the　activation　of　PMS　the　introduced　of　MoS2　effectively　promoted　the　formation　of　free　radicals　(OH,　SO4·-),　1O2　and　Fe(IV).　Due　to　the　synergistic　effects　between　Mo　and　Fe,　FeCo@MoS2　has　better　catalytic　activity　(2.01　times　larger　of　defluorination　efficiency　and　3.91　times　larger　of　the　apparent　rate　constant　(kobs))　than　FeCo.　Under　the　optimal　conditions　(catalyst　dosage　of　0.2　g　L−1,　PMS　dosage　of　1.0　g　L−1　and　initial　pH　4.0),　the　perfluorooctanoic　acid　(PFOA,　10　mg　L−1)　could　be　degraded　in　60　min,　with　90.26　±　2.64%　of　the　defluorination　efficiency.　The　LC-　MS　results　showed　that　under　the　attack　of　free　radicals　(OH,　SO4·-),　1O2　and　Fe(IV),　the　PFOA　underwent　step-by-step　defluorination　process.　In　addition,　the　ECOSAR　results　showed　that　during　the　whole　degradation　of　PFOA　in　FeCo@MoS2/PMS　system,　no　highly　toxic　intermediates　was　accumulated,　suggesting　a　green　degradation　process.　This　work　showed　new　ideas　and　strategies　for　studying　the　influence　of　polymetallic　doping　on　the　catalytic　process　of　PMS　multiphase　catalytic　system.　©　2023　Elsevier　Ltd