Two　series　of　lanthanide-carboxylates,　[Ln(2,2　＇-dtba)(2,2　＇-Hdtba)(EtOH)](n)　(I:Ln=Eu(la),　Dy(lb))　and　[Ln(2,2　＇-dtba)(2,2　＇-Hdtba)(4,4　＇-hPY)(0.5)](n)　(II:Ln=Eu(2a),　Dy(2b),　Tb(2c)　2,2　＇-H(2)dtba=2,2　＇-dithiodibenzoic　acid,　4,4　＇-bpy=4,4　＇-bipyridine)　have　been　synthesized　under　hydrothermal　conditions.　Interestingly,　the　H(2)dtba　organic　ligand　was　generated　by　in　situ　S-S　reaction　of　2-mercaptobenzoic　acid.　Compounds　I　and　II　possess　different　2D　layered　structures　based　on　similar　1D　[Ln(2,2　＇-dtba)](+)　chains.　Photoluminescence　studies　reveal　that　compounds　I　and　II　exhibit　strong　lanthanide　characteristic　emission　bands.　Remarkably,　Compounds　lb　and　2a　both　exhibit　good　photocatalytic　activity　for　degradation　of　Rhodamine-B　(Rh-B)　under　the　simulated　sunlight　irradiation.