INSITU MULTIPLE INTERNAL-REFLECTION FOURIER-TRANSFORM INFRARED SPECTROSCOPIC (MIRFTIRS) STUDY OF THE ELECTROCHEMICAL IMMOBILIZATION OF HETEROPOLYANIONS IN POLY(1-NAPHTHOL) COATED ELECTRODES

Immobilization of a Dawson-type heteropolyanion, P2W18O626- in a poly(NAP-1) film is performed by electropolymerization of 1-naphthol in the presence of an electrolyte and the corresponding heteropolyacid. In-situ i.r. analysis reveals a heterogeneous distribution of the heteropolyanion (HPA) in the polymer matrix with a larger amount at the metal-film interface. The electrochemical properties of the poly(NAP-1)/P2W18 film were studied in aqueous and organic solvents. In acidic medium, cyclic voltammetry shows three bielectronic waves from the HPA; in acetonitrile, the same transfers are observed in addition to the redox system of the polymer. In-situ MIRFTIRS spectra indicate that the electrochemical oxidation-reduction process of poly(NAP-1)/P2W18 occurs with the same structural change as for poly(NAP-1) without HPA.