A　novel　bimetallic　heterojunction　catalyst　(Co2Mo3O8/Co9S8)　with　hydrangea-like　structure　was　prepared　by　a　straightforward　one-pot　hydrothermal　and　pyrolysis　method,　which　was　then　applied　for　the　efficient　activation　of　peroxymonosulfate　(PMS)　in　wastewater　purification.　Density　functional　theory　(DFT)　simulations　revealed　that　the　formation　of　the　Co2Mo3O8/Co9S8　heterojunction　increased　the　adsorption　energy　of　PMS　and　elongated　the　O-O　bond　within　PMS.　Moreover,　an　internal　electric　field　generated　within　the　heterojunction　further　activated　PMS　through　electron-deficient　centers,　establishing　a　degradation　mechanism　primarily　dominated　by　non-radical　pathways.　Meanwhile,　the　exist　Co(II)　and　Mo(IV)　involved　as　active　sites　for　enhanced　catalytic　performance　through　the　redox　cycling　of　metal　valence　states.　In　the　optimized　Co2Mo3O8/Co9S8-PMS　system,　the　target　pollutant　doxycycline　(DOX)　was　rapidly　and　efficiently　degraded,　with　a　relatively　low　activation　energy　(3.93　kJ　&　sdot;mol-　1).　Furthermore,　the　system　demonstrated　strong　adaptability　to　interference　from　inorganic　anions,　humic　acid,　and　pH　variations,　while　effectively　removing　various　pollutants.　It　consistently　maintained　a　relatively　high　DOX　removal　efficiency　in　cyclic　experiments　and　continuous　flow　reaction　experiments.　The　present　study　provided　new　insights　for　improving　the　rational　design　of　bimetallic　heterojunction　catalysts,　and　contributed　to　a　more　effective　and　sustainable　solution　for　environmental　remediation.