Synthesis, Crystal Structure, Luminescence Sensing, and Photocatalytic Properties of a 2D Cobalt(II) Coordination Polymer Containing Bis(benzimidazole) Moieties

A new cobalt(II) coordination polymer, namely [Co(L)(Ndc)] (n) (I), where L = 1,5-bis(5,6- dimethylbenzimidazole)pentane, H(2)Ndc = 2,6-naphthalenedicarboxylic acid, was synthesized and characterized by elemental analysis, IR spectra, powder X-ray diffraction and single-crystal X-ray diffraction (CIF file CCDC no. 1548044). Complex I displays a 2D (4,4) layer which further extended into a 3D supramolecular framework via weak C-H center dot center dot center dot O hydrogen bondings. The luminescence explorations demonstrated that I exhibits highly selective and sensitive sensing for Cr2O72- with high quenching efficiency K-sv value of 9.87 x 10(3) L mol(-1) and low detection limit (0.24 mu M (S/N = 3)). Meanwhile I also exhibits highly selective and sensitive sensing for Fe3+ with quenching efficiency K (sv) = 3.6 x 10(4) L mol(-1) and low detection limit (0.32 mu M (S/N = 3)). Complex I exhibits higher photocatalytic activities for the degradation of methylene blue under UV irradiation. Additionally, the thermal behavior and electrochemical properties of the compound are also presented.