Molecular　doping　of　conjugated　carbon　nitride　(CN)　with　thiophene　donors　was　applied　for　the　modification　of　CN　photocatalysts.　The　incorporation　of　electron-rich　thiophene　entities　in　the　conjugated　polymer　matrix　can　effectively　change　the　intrinsic　bulk　and　surface　features　of　CN,　such　as　engineering　the　electronic　structure　with　tunable　bandgap　and　promoting　the　charge-carrier　migration　and　separation　via　forming　surface　dyadic　structures.　A　significant　alteration　in　the　texture,　morphology,　and　crystalline　was　also　observed　for　the　thiophene-modified　CN　samples.　The　combined　benefits　of　the　molecular　doping　in　terms　of　bulk,　surface,　and　texture　properties　lead　to　an　improvement　in　the　photocatalytic　activity　for　H-2　generation　with　visible　light,　which　underlines　the　importance　of　organic　chemistry　protocols　for　the　chemical　modification　of　newly　developed　metal-free,　polymeric　photocatalysts.　(C)　2013　Elsevier　Inc.　All　rights　reserved.