Catalysts in fuel cells are normally platinum based because platinum exhibits high electrocatalytic activity towards ethanol oxidation in acidic medium. However, bulk Pt is expensive and rare in nature. To reduce the consumption of Pt, a support material or matrix is needed to disperse Pt on its surface as micro- or nanoparticles with potential application as anode material in direct ethanol fuel cells (DEFCs). In this study, a composite material consisting of platinum particles dispersed on reduced graphene oxide/poly(3,4-ethylenedioxythiophene) (RGO/PEDOT) support was electrochemically prepared for ethanol oxidation in sulfuric acid electrolyte. PEDOT, a conductive polymer, was potentiodynamically polymerized from the corresponding monomer, 0.10？M EDOT in 0.10？M HClO4 electrolyte. The PEDOT-modified electrode was used as a substrate for exfoliated graphene oxide (EGO) which was prepared by electrochemical exfoliation of graphite from carbon rod of spent batteries and subsequently reduced to form RGO. The Pt/RGO/PEDOT composite gave the highest electrocatalytic activity with an anodic current density of 2688.7？mA·cm？2 at E？=？0.70？V (versus Ag/AgCl) towards ethanol oxidation compared to bare Pt electrode and other composites. Scanning electron microscopy (SEM) revealed the surface morphology of the hybrid composites while energy dispersive X-ray (EDX) confirmed the presence of all the elements for the Pt/RGO/PEDOT composite. 1. Introduction Fuel cells are basically open thermodynamic systems that operate on the basis of electrochemical reactions and consume reactant from an external source, simply its fuel. In the recent years, proton exchange membrane fuel cells (PEMFCs) have been extensively studied and emerged as one of the potential systems, which not only provide clean energy but also offer good commercial feasibility and portability [1]. Direct alcohol fuel cell (DAFC) is a variety of PEMFCs which uses alcohols such as methanol and ethanol. Alcohols have low molecular weight and can be stored in dilute concentrations as fuel has been noted for portability and transportation applications. Direct ethanol fuel cells (DEFCs) have spurred more and more interest in recent years due to ethanol’s intrinsic advantages such as low toxicity, renewability, and its easy production in great quantity by the fermentation from sugar-containing raw materials [2]. Moreover, catalysts such as precious metals and nonprecious metals are needed for the oxidation of ethanol. Platinum (Pt) has currently been regarded as the best catalyst for fuel cell electrochemical
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