Syntheses, structural diversity and photocatalytic properties of two rare Ni(II) coordination polymers assembled by "V"-shaped dicarboxylates and bis(imidazolyl) ligands

novel coordination polymers, namely {[Ni-2(dpb)(Hdpb)(2)(4,4'-bbibp)(2)(H2O)]center dot H2O). (1) and [Ni(dpb)(bimb)(H2O)](infinity) (2) (H(2)dpb = 3,5-di(4'-carboxyl-phenyl)benzene acid, 4,4'-bbibp = 4.4'-bis(benzoimidazo-1-ly)biphenyl, bimb = 1,4-bis(imidazol-1-ylmethyl)benzene) have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Complex 1 shows a rare 1D meso-helical ladder chain, and the adjacent 1D irregular ladder chain forms a 3D supramolecular framework through the O-H center dot center dot center dot O and O-H center dot center dot center dot pi interactions. Complex 2 exhibits an unprecedented 2-nodal (2,4)-connected 2D layer structure with the Schlafli point symbol (8(4)center dot 12(2))(8(2)), which are further assembled into a 3D supramolecular structure also by O-H center dot center dot center dot O interactions. Furthermore, the photocatalytic properties of complexes 1 and 2 have been investigated. Interestingly, complex 2 not only shows an remarkable photocatalytic activity on RhB/MB degradation, but also has a better adsorption activity based on the bigger channel under magnetically stirred in the dark for 30 min. (C) 2016 Elsevier B.V. All rights reserved.