Synthesis,Structure, Photoluminescence and Photocatalytic Properties of a New Cd(Ⅱ) Metal-organic Framework Based on 1,4-Di(2,6-dimethyl-3,5-dicarboxypyridyl)benzene

A new 3D coordination polymer, Cd_2(L)(bpb)_2]_n(1, H_4L = 1,4-di(2,6-dimethyl-3,5-dicarboxypyridyl) benzene, bpb = 1,4-bis(4-pyridyl) benzene, has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, TGA, IR spectroscopy and UV-Vis spectrum. Complex 1 crystallizes in orthorhombic, space group C2221, with a = 10.9393(12), b = 20.900(3), c = 20.027(2) ?, β = 90°, V = 4578.9(9) ?~3, Dc = 41.668 Mg/cm~3, M_r = 1149.74, F(000) = 2312.0, μ = 0.996 mm~(–1), Z = 4, the final R = 0.0316 and wR = 0.0786 for 4271 observed reflections with I 2σ(I). Structural analysis shows that 1 possesses a 3D network based on the 2D layer bridged by L~4-ligands, while the 2D layers are composed of the adjacent 1D chains joined by L~4-ligand. The photoluminescent investigation indicates that one broad emission band with the maximum of 445 nm can be observed in 1. Moreover, compound 1 has high photocatalytic degradation effects on methylene blue under UV irradiation.