Preparation of noble metal supported carbon electrodes using photochemically reduced heteropolyanions in composite films

A novel reduction technique is developed for preparing a Pt/C system using organic-inorganic nanocomposite consisting of heteropolyanions. Transmission electron microscopic studies revealed the formation of anisotropic platinum nanocrystals. Cyclic voltammetry and electrochemical impedance spectroscopy were employed to evaluate the electrochemical methanol oxidation over the prepared Pt/C electrode. The obtained Pt/C catalysts were found to exhibit higher activity and stability for methanol oxidation in perchloric acid than in sulphuric acid medium. The activation energy for methanol oxidation was found to be 41 ± 3 kJ mol−1, being lower than the reported value. The lower activation energy for methanol oxidation on Pt/C could be attributed to the presence of anisotropic platinum nanoparticles.