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

摘要

Using a hemi-rigid multitopic ligand, 1,3,5-triazine-2,4,6-triyltrithio- triacetic acid (H_3L), three metal(ii)-complexes formulated as Pb _2L(ox)_(1/2)(H_2O) (H_2ox = oxalic acid) (1), Pb_3L_2(H_2O)_2 (2) and Ni _6L_4(PEP)_6(H_2O)_(12)· 7H_2O (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 (4~2.6~3.8)(4 ~2.6~8)_2(4~2.6)_2(4 ~3.6~(11).8_2 topology and complex 2 presents a 3-nodal (5, 6, 8)-connected 3D framework with a novel (3.4~4.5 3.6~2)(3~3.4~(12).5~5.6 ~8)(3~5.4~7.5~3) 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 (6.7 ~2)_2(6~4.7.8)_2(7~4.8.10) topology. L~(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.