The　development　of　durable　and　highly　efficient　visible-light-driven　photocatalysts　is　essential　for　the　photocatalytic　ozonation　process　towards　degrading　organic　pollutants.　This　study　presents　CN-MA,　a　novel　photocatalyst　synthesized　by　grafting　carbon　nitride　(CN)　with　single-atom　Mn　and　2-hydroxy-4,6-dimethylpyrimidine　(HDMP)　via　one-step　thermal　polymerization.　Experimental　characterization　and　theoretical　calculation　results　reveal　that　incorporating　single-atom　Mn　and　HDMP　into　CN　alters　the　charge　density　distribution　on　the　heptazine　rings.　This　modification　enhances　the　absorption　of　visible　light　and　reduces　exciton　binding　energy,　leading　to　improved　separation　and　migration　of　photogenerated　charge　carriers.　Moreover,　the　single-atom　Mn　provides　abundant　active　sites　for　O3　adsorption　and　activation,　which　increases　the　utilization　of　photogenerated　electrons　to　produce　highly　reactive　oxidative　species.　Consequently,　CN-MA　exhibits　superior　photocatalytic　ozonation　activity,　achieving　94%　mineralization　of　phenol　within　60　min　and　maintaining　excellent　stability　over　multiple　cycles.　The　research　also　proposes　a　plausible　reaction　mechanism　based　on　free-radical　trapping　experiments　and　steady-state　concentration　experiments　using　molecular　probes.　This　strategy　advances　the　development　of　molecular-engineered　catalysts　co-modified　with　single　metal　atoms,　thereby　enhancing　the　photocatalytic　ozonation　process　for　the　degradation　of　organic　pollutants.　©　2024　Elsevier　Inc.