The world’s demand for energy has increased dramatically over the last few decades, and will continue to do so. Therefore, it is urgent to find alternative energy sources and perhaps unconventional way of energy conversion with much improved energy efficiency [1]. Fuel cells have received increasing attention because of their high energy-conversion efficiency and environmental affinity [2]. Among different type of fuel cells, direct alcohol fuel cells (DAFCs) were attracting increasing interest as a compact power sources for portable applications, mainly due to the relatively simple handling, storage, and transportation of the fuel [3]. In this study, a nanocomposite surface coating was prepared by electropolymerization of pyrrole by cycling the electrode potential between –0.8 and 0.8 V (vs. SCE). Then its surface was potentiostatically coated with platinum nanoparticles at constant potential of –0.2 V (vs. SCE). The resulting electrode was referred as GCE/PPy/Pt. The microscopic structure and morphology of the polypyrrole (PPy) film was characterized by scanning electron microscopy. The platinum nanoparticles were uniformly dispersed in PPy matrixes, as confirmed by transmission electron microscopy. Energy dispersive X-ray (EDX) analysis was used to confirm the presence of platinum nanoparticles in PPy film. The electrochemical and catalytic activities of the GCE/PPy/Pt were compared with GCE/Pt in 0.3 M HClO4 solution. The electrooxidation of ethanol on the GCE/PPy/Pt was studied by means of electrochemical techniques. The modified electrode exhibits a significant eletrocatalytic activity for ethanol oxidation compared to the other electrodes used in this study. The enhanced electrocatalytic activities may be due to the uniform dispersion of platinum nanoparticles in the PPy film. The effects of various parameters on electrocatalytic oxidation of the ethanol such as the thickness of PPy film, the amount of platinum nanoparticles, ethanol concentration, potential scan rate and the working potential limit in anodic direction were investigated. Finally the Tafel studies of ethanol oxidation are discussed.

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