title: Construction of noninterpenetrating and interpenetrating Co(ii) networks with halogenated carboxylate modulated by auxiliary N-donor co-ligands: structural diversity, electrochemical and photocatalytic properties.
abstract: Six Co(ii)-based coordination polymers (CPs) with characteristic frameworks and topologies-namely, [Co(L1)(DCTP)]n(1), [Co(L2)(DCTP)]n(2), [Co(L3)(DCTP)]n(3), {[Co3(L4)3(DCTP)3·H2O]·H2O}n(4), [Co(L5)1.5(DCTP)]n(5) and [Co(L6)(DCTP)]n(6)-were successfully hydrothermally synthesized by employing the halogenated linear ligand 2,5-dichloroterephthalic acid (H2DCTP). The interpenetrated structures could be rationally modulated by auxiliary N-donor co-ligands containing 1,1'-(1,4-butanediyl)bis-1H-benzimidazole (L1), 1,4-bis(5,6-dimethylbenzimidazol-1-yl)-2-butylene (L2), 1,2-bis(2-methylbenzimidazol-1-ylmethyl)benzene (L3), 1,4-bis(2-methylbenzimidazol-1-ylmethyl)benzene (L4), 1,2-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene (L5) and 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene (L6). These diaphanous crystals were clearly characterized by elemental analysis, infrared (IR) spectra and X-ray powder diffraction (XRPD) as well as single-crystal X-ray diffraction analysis. With the aid of the flexible N-donor co-ligands, CP 1 occupies a non-interpenetrated 2D sheet with the point symbol {44·62} sql net topology, CP 2 possesses a 3D hexagon-shaped network with the point symbol {66} three-fold interpenetrated sqc6 topology, CP 3 exhibits a 2D layer with the point symbol {44·62} sql net topology, CP 4 reveals an unusual 3D framework with the point symbol {42·63·8} three-fold interpenetrated sra topology, CP 5 has a 3D hexagon-shaped network with the point symbol {66} two-fold interpenetrated sqc6 topology, while CP 6 displays a 3D hexagon-shaped network with the point symbol {66} three-fold interpenetrated sqc6 topology. The diverse structures of CPs 1-6 illustrate that the substitute group and position of the methyl group of the bis(benzimidazole) derivatives play a significant role in the assembly of such interpenetrated frameworks. Moreover, luminescence properties and thermal behavior, as well as the electrochemical and photocatalytic properties of CPs 1-6 on the degradation of methylene blue, are also presented.
authors.affiliation: College of Chemical Engineering, Hebei Key Laboratory for Environment Photocatalytic and Electrocatalytic Materials, North China University of Science and Technology, Tangshan Hebei 063009, P. R. China. tscghua@126.com.
authors.forename: Shao Yun
authors.initials: SY
authors.lastname: Hao
authors.affiliation: College of Chemical Engineering, Hebei Key Laboratory for Environment Photocatalytic and Electrocatalytic Materials, North China University of Science and Technology, Tangshan Hebei 063009, P. R. China. tscghua@126.com.
authors.forename: Suo Xia
authors.initials: SX
authors.lastname: Hou
authors.affiliation: XStruct, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281-S3, 9000 Ghent, Belgium.
authors.forename: Kristof
authors.identifier: http://orcid.org/0000-0002-2455-8856
authors.initials: K
authors.lastname: Van Hecke
authors.affiliation: College of Chemical Engineering, Hebei Key Laboratory for Environment Photocatalytic and Electrocatalytic Materials, North China University of Science and Technology, Tangshan Hebei 063009, P. R. China. tscghua@126.com.
authors.forename: Guang Hua
authors.identifier: http://orcid.org/0000-0001-9624-5990
authors.initials: GH
authors.lastname: Cui