Ferrimagnetic copper-carboxyphosphinate compounds for catalytic degradation of methylene blue

Abstract

Two novel coordination polymers have been hydrothermally synthesized by reactions of Cu(II) salt with 2,2′-phosphinico-dibenzoic acid (H3L), namely, [Cu6L4(H2O)10]·8H2O (1) and [Cu3L2(4,4′-bipy)2(H2O)2] (2). Both compounds were well characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopic, powder X-ray diffraction and thermal analyses. Compound 1 crystallizes in a noncentrosymmetric monoclinic Pc space group and presents a ladder-like chain structure. In the structure of 1, Cu6 ions are attached to one side of the ladder through carboxylate group generating a novel noncentrosymmetric chain. Magnetic studies indicate that compound 1 exhibits a typical ferrimagnetic behavior. Compound 2 crystallizes in a monoclinic P21/c space group and presents a three-dimensional framework architecture. Compounds 1 and 2 show catalytic activities for the degradation of methylene blue in aqueous solution.