Synthesis and electrochemical properties of an interdigitated architecture based on Keggin phosphotungstates

A new coordination polymer, [Cu2(μ1-bipy)2(μ2-bipy)(μ1-H2O)2(μ2-OH)2(HPW12O40)]⋅4H2O (1) (bipy = 4,4′-bipy), has been synthesized in hydrothermal condition and characterized by elemental analysis, IR spectrum, TG analysis, powder X-ray diffraction and single crystal X-ray diffraction. In 1, the Keggin PW12 clusters as bidentate connectors link dinuclear copper(II) complexes to form a two-dimensional (2D) framework, in which the monocoordinated bipy molecules are orderly appended to both sides of the layer, respectively. Adjacent layers mutually engage in a zipper-like pattern to generate a new 2D + 2D → 3D interdigitated architecture, which represents the first interdigitated architecture assembled by Keggin phosphotungstate clusters and dinuclear copper(II) complexes. Furthermore, the electrochemical properties of 1 were studied, which indicate that 1 has a good electrocatalytic activity toward reduction of hydrogen peroxide.