Developing　photocatalytic　hydrogen　evolution　technology　based　on　graphitic　carbon　nitride　(g-C3N4,　CN)　has　emerged　as　a　potential　solution　for　the　future　energy　shortage　in　recent　years.　Herein,　carbon　(C)　and　fluorine　(F)　co-doping　graphitic　carbon　nitride　nanosheets　(CFCN)　were　synthesized　via　a　one-pot　co-thermal　method　without　introducing　any　metal　element.　Exceptional　hydrogen　production　activity　(3.87　mmol/h/g)　was　achieved　by　CFCN　under　visible　light　irradiation,　which　was　4.2-fold　increase　compared　to　the　pristine　CN.　It　could　be　attributed　to　the　large　specific　surface　area　(51.59　m2/g)　and　efficient　mass　transfer　facilitated　by　the　porous　sheet-like　morphology　of　CFCN.　Additionally,　the　modification　of　the　band　structure　and　internal　charge　redistribution　were　investigated　via　density　functional　theory　(DFT)　calculations,　which　confirmed　there　was　a　unidirectional　and　fast　electron　transfer　channel　from　N　through　the　C4　delocalized　large　π　bond　to　F.　This　creative　research　uncovered　the　pivotal　role　of　F/C　co-doping　in　enhancing　photocatalytic　hydrogen　evolution　efficacy,　offering　cutting-edge　insights　into　the　design　of　sustainable　and　eco-friendly　photocatalysts　based　on　metal-free　CN.　©　2024　Elsevier　B.V.