Photocatalytic　aerobic　oxidation　of　alcohols　for　the　direct　synthesis　of　esters　has　received　significant　attention　in　recent　years,　but　the　relatively　low　efficiency　and　selectivity　under　visible　light　irradiation　is　the　main　challenge　for　their　practical　applications.　Here,　surface　acidic　sites　were　imparted　onto　metal-free　heterogeneous　photocatalysts　by　the　protonation　of　carbon　nitride　(HMCN)　to　promote　the　activity　for　the　esterification　reaction　through　further　adsorption　and　activation　of　the　intermediate　alde-hyde.　The　activation　of　the　substrate　could　be　remarkably　modulated　through　tuning　the　acidic　sites　on　the　surface　of　the　photocatalyst,　leading　to　a　controllable　reactivity　of　the　catalytic　reaction.　The　one-pot　process　for　the　direct　aerobic　oxidative　esterification　of　alcohol　exhibits　high　efficiency　and　selectivity　under　mild　and　additive-free　conditions　and　the　apparent　quantum　yield　(AQY)　of　the　photocatalytic　esterification　reaction　is　0.41%　at　420　nm.　Moreover,　a　scalable　photocatalytic　process　by　the　merging　of　a　continuous　flow　system　with　the　heterogeneous　HMCN　photocatalyst　is　demonstrated,　combining　high　catalytic　efficiency　and　stability　at　ambient　temperatures　and　being　promising　for　larger-scale　applications.　(c)　2020　Elsevier　Inc.　All　rights　reserved.