Oxygen reduction reaction on Pt-Pd catalysts supported on carbon xerogels: Effect of the synthesis method

In this work, Pt-Pd nanoparticles supported on carbon xerogels (Pt-Pd/CX) were synthesised employing unusual routes, in order to evaluate its activity toward the oxygen reduction reaction (ORR). The synthesis methods produced materials with the planned composition (metal content close to 40 wt % and Pt:Pd atomic ratios around 1:2), with Pt, Pd and alloyed Pt-Pd nanoparticles well dispersed on the carbon support. The content of Pt in the nanoparticles was optimised through these procedures, placing this metal at the surface. As a consequence, the Pt-Pd/CX catalysts displayed high activity toward the ORR and remarkable resistance to corrosion, overcoming the electrocatalytic properties of a commercial Pt/C catalyst. Moreover, these catalysts involve four electrons in the ORR. Therefore, the study here presented indicated that the as-synthesised Pt-Pd/CX catalysts are suitable candidates to be employed as cathodes in proton exchange membrane fuel cells.