In　this　study,　sludge-derived　biochar　loaded　Co3O4　composite　(Co3O4@SDBC)　were　successfully　synthesized　through　cobalt　impregnation　and　secondary　calcination　of　sludge-derived　biochar　precursors.　The　experimental　results　demonstrated　that　the　Co3O4@SDBC　catalyst　performed　exceptionally　well　for　peroxymonosulfate　(PMS)　activation,　with　a　high　degradation　efficiency　(＞99　%)　of　ofloxacin　(OFL)　within　10　min　under　the　optimal　conditions　(a　catalyst　dose　of　0.10　g•L−1,　a　PMS　dose　of　0.975　mM　and　an　initial　pH　=　6.4),　and　showed　good　adaptability　across　a　broad　pH　spectrum,　under　the　interference　of　the　anions　and　humic　acid　(HA),　as　well　as　in　various　water　matrices.　The　results　of　quenching　experiments　revealed　that　the　non-radical　pathway　(especially　1O2　and　electron　transfer)　was　the　dominated　reactive　ingredients　in　the　PMS　activation　process　induced　by　Co3O4@SDBC.　Notably,　the　online　electrochemical　tests　and　density　functional　theory　(DFT)　results　indicated　the　presence　of　biochar　carrier　not　only　effectively　lowered　the　escape　of　Co　ions,　while　enhanced　the　steadiness　of　Co3O4@SDBC,　but　also　accelerated　the　electron　transfer,　promoted　the　adsorption　and　cleavage　of　PMS,　facilitated　the　redox　cycle　between　Co(II)　and　Co(III),　reduced　the　reaction　energy　barriers　simultaneously,　thereby　making　it　more　favourable　for　the　generation　of　1O2.　Furthermore,　the　toxicity　assessment　suggested　that　the　cumulative　toxicity　of　OFL　decreased　throughout　degradation.　Overall,　this　work　mechanistically　revealed　the　enhancement　of　biochar　on　the　Co3O4@SDBC　catalyst,　offering　a　viable　method　to　activate　PMS　for　antibiotic　removal　and　achieving　a　mutually　beneficial　strategy　for　sludge　waste　resource　utilization　and　environmental　remediation.　©　2024　Elsevier　B.V.