Pseudohalide-directed assemblies of Cu(II) coordination polymers with diverse structures and dye adsorption behaviors

Abstract

Assembly of 3,4-bis(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (L334) and CuBr2 without or with the presence of thiocyanate (SCN−)/dicyanamide [dca, N(CN)2−] anion produces three Cu(II) coordination polymers, {[Cu(L334)(H2O)2](Br)2(CH3OH)}n (1), {[Cu(L334)(SCN)2(H2O)](H2O)(EA)}n (2) (EA = ethyl acetate), and [Cu(L334)(dca)2]n (3). The crystal structures for 1 and 3 show different 2D layered coordination networks, whereas that for 2 represents a distinct 1D coordination pattern. The above results demonstrate that the addition of pseudohalide anions plays an important role in structural construction of coordination architectures. Moreover, 1 exhibits the best adsorption capacity toward methyl orange (MO) dye.