Synthesis of Ordered Mesoporous Carbon As Support for Pt-Co Alloys: Evaluation As an Alcohol-Tolerant ORR Catalyst for Direct Oxidation Fuel Cells

One of the most important drawbacks for the commercialization of low temperature Direct Oxidation Fuel Cells (DOFCs) is the crossover of liquid fuels through commercially available polymer electrolyte membranes. In these cells Pt-alone electrocatalyst is rapidly poisoned by such substances and/or their intermediates. The investigations on this matter include the development of tolerant cathodes based on Pt alloys which have shown a high catalytic activity for the ORR. Ordered Mesoporous Carbon (OMC) has received great attention because of their potential use as electrocatalysts support for fuel cell electrodes due to their relatively large pores that facilitate mass transfer, and their very high surface area, which allows a high concentration of active sites per mass of catalyst. OMC was synthesized via self-assembly in aqueous phase using Resorcinol/Formaldehyde as carbon precursors, followed by pyrolysis at high temperature. Pt-Co catalysts supported on OMC (Pt-Co/OMC) were synthesized by the polyol reduction process. Pt-Co/OMC catalyst was characterized by X-ray diffraction, scanning electron microscope-energy dispersive X-ray analysis, and transmission electron microscopy techniques. The electrocatalytic behavior for the ORR was investigated in rotating disk electrode configuration in an acidic medium. In the presence of the different liquid fuels (ethanol, ethylene glycol or 2-propanol), the alloys show a high degree of tolerance. The results obtained from the Pt-Co/OMC electrocatalysts were compared to those of a Pt/OMC cathode.