Synthesis, structure, and photocatalytic properties of a Cu(II) coordination polymer derived from a flexible tripodal linker

A copper coordination polymer, {[Cu(TIB)₂(H₂O)₂].Cl₂(H₂O)₂}_n (CP1) involving a tripodal N-donor, 1,3,5-tris((1H-imidazol-1-yl)methyl)benzene (TIB) ligand has been synthesized by environmentally friendly methods and structurally characterized. CP1 exists as a 1D coordination polymer in which the Cu(II) ions possess a distorted octahedral coordination environment provided by N atoms from the four TIB ligands constituting the square base and O atoms from two coordinated water molecules occupying the axial coordination sites. The packing and hydrogen bonding interaction of CP1 revealed that the centrosymmetric metal-organic strands are involved in intermolecular hydrogen bonding in the formation of 3D network via O-H···N, O-H···Cl and π···π interactions. CP1 also features a [(H₂O)₂Cl₂] cluster running down the c-axis, i.e., parallel to the metal-organic strands, [Cu(TIB)₂(H₂O)₂]_n. CP1 is characterized by single-crystal X-ray diffraction and other physico-chemical techniques. Photocatalytic activity of CP1 for the decomposition of aqueous Aniline Blue (AB) in the presence of 1 M hydrogen peroxide under the LED illumination was examined and showed approximately 62 % dye degradation in 135 min.