Metal–organic frameworks based on 1,3,5-triazine-2,4,6-triyltrithio-triacetate: structures, topologies, photoluminescence and photocatalytic properties

Using a hemi-rigid multitopic ligand, 1,3,5-triazine-2,4,6-triyltrithio-triacetic acid (H33333L), three metal(II)-complexes formulated as Pb2L(ox)1/2(H2O) (H2ox = oxalic acid) (1), Pb3L2(H2O)2 (2) and Ni6L4(PEP)6(H2O)12·7H2O (PEP = 4-(2-(pyridin-4-yl)ethyl)pyridine) (3) have been hydro(solvo)thermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 features a novel 4-nodal (3, 4, 5, 6)-connected 3D framework with an unusual (42.63.8)(42.68)2(42.6)2(43.611.8)2 topology and complex 2 presents a 3-nodal (5, 6, 8)-connected 3D framework with a novel (3.44.53.62)(33.412.55.68)(35.47.53) topology. Complexes 1 and 2 are hybrid Pb oxides, in which a 2D Pb–O–Pb layer is observed. Complex 3 shows a 3-nodal (3, 4)-connected 3D framework with a novel (6.72)2(64.7.8)2(74.8.10) topology. L3−3− displays different coordination modes in the three complexes. Complexes 1 and 2 show different UV absorptions, emission spectra, photoluminescence lifetimes and they are photocatalytically active for the decomposition of methyl orange (MO) under UV light irradiation.