Supramolecular Association between γ-Cyclodextrin and Preyssler-Type Polyoxotungstate

Abstract

The development of hybrid materials based on polyoxometalates constitutes a strategy for the design of multifunctional materials. The slow evaporation of an aqueous solution of [NaP5W30O110]14− in the presence of γ-Cyclodextrin (γ-CD) led to the crystallization of a K6Na8{[NaP5W30O110]•(C48H80O40)}•23H2O (NaP5W30•1CD) supramolecular compound, which was characterized by single-crystal X-ray diffraction, IR-spectroscopy, thermogravimetric and elemental analyses. Structural analysis revealed the formation of 1:1 {[NaP5W30O110]•[γ-CD]}14− adduct in the solid state. Studies in solution by cyclic voltammetry, electrochemical impedance spectroscopy, 1H NMR spectroscopy, and 31P DOSY, have demonstrated weak interactions between the inorganic anion and the macrocyclic organic molecule.

Keywords

• polyoxometalate
• supramolecular adduct
• XRD structure
• NMR spectroscopy
• cyclic voltammetry
• electrochemical impedance spectroscopy