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Phosphomolybdate has been employed simultaneously as the oxidizing agent for the monomer polymerization and the reduced polyoxometalate is used as reducing agent for the reduction of metal ions. The composites thus obtained have been characterized and may have many potential applications.

Tungsten trioxide nanorods have been generated by the thermal decomposition (450 °C) of tetrabutylammonium decatungstate. The synthesized tungsten trioxide (WO3) nanorods have been characterized by XRD, Raman, SEM, TEM, HRTEM and cyclic voltammetry. High resolution transmission electron microscopy and X-ray diffraction analysis showed that the synthesized WO3nanorods are crystalline in nature with monoclinic structure. The electrochemical experiments showed that they constitute a better electrocatalytic system for hydrogen evolution reaction in acid medium compared to their bulk counterpart.

The abilities of Keggin type polyoxometalate, silicotungstic acid (STA) to reduce metal ions by electron transfer and to modify carbon surface by strong adsorption have been explored for the preparation of Pt nanoparticles supported on carbon composites (20% Pt/STA-C). The prepared composites were characterized by Transmission electron microscopy (TEM and HRTEM)), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The electrocatalytic activities of the prepared nanocomposites were examined by using Cyclic voltammetry (CV) for oxygen reduction reaction which takes place at cathode in fuel cells. The prepared composite (20% Pt/STA-C) proved efficient compared to STA free 20% Pt/C, prepared by hydrogen reduction method. H2O2 intermediate formation is a serious concern as it reduces the activity of Pt sites during oxygen reduction. The composites prepared by polyoxometalate reduction method (20% Pt/STA-C) showed better reduction ability towards H2O2 compared to STA free 20% Pt/C composite and thus showed better performance as cathode electrocatalyst for fuel cells.

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