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Ethanol is a molecule of considerable interest because of its potential renewable use in fuel cells without reforming. Therefore, bifunctional electrocatalysts were proposed to decrease the precious noble metal content in the catalyst composition and to promote the conversion of this fuel, leading to the preparation of Pt-based materials containing oxophilic co-catalysts such as tin, osmium, iridium and ruthenium. They allow the ethanol oxidation to occur at low potentials, and also remove CO-like adsorbed species from the electrode surface. The knowledge of the mechanism is important to propose new materials and design that are able to promote the cleavage of the C-C bond in large extent. This chapter discusses the performances obtained in a single direct ethanol fuel cell (DEFC) using various Pt-based anode nanomaterials for oxidizing ethanol in acidic environment. It shows the recent progress in catalyst preparation, particularly the thermal decomposition and microwave heating methods. The activity of the electrocatalysts is discussed by examining their capability of converting ethanol to different reaction products. Great attention is paid to the identification of the reaction intermediate species and those in the bulk by using in situ infrared spectroscopy and other analytical techniques. Performance in a DEFC is a direct measurement between the anodic and cathodic potentials which depends on the ethanol oxidation occurring at low overpotentials and also on the oxygen reduction reaction (ORR) at higher ones. Determination of the kinetic parameters for the ORR and quantitative detection of hydrogen peroxide formation with rotating ring disk electrode technique are herein proposed as an overview of the electrode kinetics.