Synthesis, structure and electrochemical properties of a polyoxometalate-templated compound with 2D twofold interpenetrating network.

new Keggin-type polyoxometalate-based compound {[Cu( L)(HO)](PWWO)}·16HO ( 1) constructed from PWWO, N,N′-bis(4-pyridylformyl) piperazine ( L) and Cu(II) has been hydrothermally synthesized and structurally characterized by elemental analyses, IR and single-crystal X-ray diffraction analysis. Single-crystal X-ray diffraction analysis reveals that the semi-rigid piperazine-based ligands L coordinate to the Cu(II) atoms to constitute a two dimensional coordination network. The 2D (4, 4) cationic layers are stacked together in a perpendicular mode, resulting in the formation of twofold interpenetrating frameworks with large cavities. The PW anions reside in the large cubic-like cavities, serving as non-coordinating templates. The compound 1 displays good electrocatalytic activity toward the reduction of nitrite in 1 M HSO aqueous solution. [ABSTRACT FROM AUTHOR]