Four Co(II) coordination polymers based on 4,4 '-bis(benzimidazol-1-ylmethyl)biphenyl and aromatic carboxylic acids co-ligands: Synthesis, structures, and photocatalytic properties

摘要

Four Co(II) coordination polymers, [Co(L)(2)(1,4-bdc)](n) (1), [Co-0.5(HL)(Hbtc)](n) (2), {[Co(L)(1,3-bdc)(H2O)]center dot 1.5H(2)O}(n) (3) and {[Co-2(L)(2)(nip)(2)]center dot 2H(2)O}(n) (4) (L = 4,4'-bis(benzimidazol-1-ylmethyl)biphenyl, 1,4-H(2)bdc = 1,4-benzenedicarboxylic acid, H(3)btc = 1,3,5-benzenetricarboxylic acid, 1,3-H(2)bdc = 1,3-benzenedicarboxylic acid, H(2)nip = 5-nitroisophthalic acid) have been synthesized under hydrothermal reaction conditions. Both complexes 1 and 2 feature chain structures, and 2 is ultimately extended into a 2D supramolecular framework via classic hydrogen bonding interactions. Complex 3 possesses a (4,4) grid with {4(4).6(2)} topology. Complex 4 displays a 2D (6,3) layer, which is further extended into a 3D supramolecular network with unusual binodal (3,4)-connected sqc1425 topology via O-H center dot center dot center dot O hydrogen bonding interactions. Additionally, the thermal stability, UV/Vis diffuse-reflection spectra and photocatalytic behaviors of these CPs have also been investigated. (C) 2016 Elsevier B.V. All rights reserved.