Photochemistry　provides　a　sustainable　pathway　for　organic　transformations　by　inducing　radical　intermediates　from　substrates　through　electron　transfer　process.　However,　progress　is　limited　by　heterogeneous　photocatalysts　that　are　required　to　be　efficient,　stable,　and　inexpensive　for　long-term　operation　with　easy　recyclability　and　product　separation.　Here,　we　report　that　boron　carbonitride　(BCN)　ceramics　are　such　a　system　and　can　reduce　organic　halides,　including　(het)aryl　and　alkyl　halides,　with　visible　light　irradiation.　Cross-coupling　of　halides　to　afford　new　C-H,　C-C,　and　C-S　bonds　can　proceed　at　ambient　reaction　conditions.　Hydrogen,　(het)aryl,　and　sulfonyl　groups　were　introduced　into　the　arenes　and　heteroarenes　at　the　designed　positions　by　means　of　mesolytic　C-X　(carbon-halogen)　bond　cleavage　in　the　absence　of　any　metal-based　catalysts　or　ligands.　BCN　can　be　used　not　only　for　half　reactions,　like　reduction　reactions　with　a　sacrificial　agent,　but　also　redox　reactions　through　oxidative　and　reductive　interfacial　electron　transfer.　The　BCN　photocatalyst　shows　tolerance　to　different　substituents　and　conserved　activity　after　five　recycles.　The　apparent　metal-free　system　opens　new　opportunities　for　a　wide　range　of　organic　catalysts　using　light　energy　and　sustainable　materials,　which　are　metal-free,　inexpensive　and　stable.　This　journal　is　©　The　Royal　Society　of　Chemistry.