Syntheses, structures, photocatalysis properties and photoluminescent properties of four two-dimensional functional coordination polymers based on a semi-rigid tetracarboxylic acid

Abstract

Four two-dimensional functional coordination polymers, namely [Co(H2L)(bibp)(H2O)]n (1), {[Ni(H2L)(bibp)(H2O)]·0.5H2O}n (2), [Co2(L)(bimb)]n (3) and [Zn2(L)(bimb)]n (4) (H4L=5,5′-(1,3-phenylenebis(methoxy))diisophthalic acid, bibp=4,4′-bis(imidazolyl)biphenyl, bimb=1,4-bis(imidazol)-butane) have been successfully hydrothermally synthesized. All of these four polymers were characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. All of the four CPs are shown the rare 2D+2D→2D network. Complexes 1 and 2 have the similar structures with the same new topological framework with the point symbol [44. 62] [4]2; complexes 3 and 4 are isomorphous and display [M2(COO)2(bimb)] (M=Co for 3, Zn for 4) binuclear SBUs based on sq1 framework with the point symbol [44. 62]. Moreover, the photocatalytic degradation of four Co(II) complexes 1–4 have been investigated.