Synthesis, characterization and dye adsorption property of a 2D nickel(ii)-coordination polymer constructed from tetracarboxylic acid and 1,3-bis(imidazol-1-yl-methyl)benzene

Abstract

A new Ni(II)-coordination polymer, {[Ni₂(μ₄-L)(μ-mbix)₂]·2H₂O}_n (1), was synthesized using (E)-5,5′-(but-2-ene-1,4-diylbis(oxy))diisophthalic acid (H₄L) and 1,3-bis(imidazol-1-yl-methyl)benzene (mbix) ligands in the presence of Ni(II) ions. Compound 1 was characterized using elemental analysis, FTIR spectroscopy, and single crystal and powder X-ray diffraction techniques. The single crystal X-ray diffraction analysis revealed that compound 1 demonstrated a 2D structure with the kgm topology with the vertex symbol of 3²·6²·7². The adsorption behavior of 1 toward cationic methylene blue dye was investigated using diverse adsorption parameters. A maximum MB decolorization efficiency of 79% was achieved at pH = 10 in 60 min. MB removal with compound 1 can be attributed to electrostatic interactions between the cationic MB dye and 1, which has a negative charge density on the surface. The adsorption kinetics and isotherms were also studied using experimental data.