Performance of carbon-supported palladium and palladium ruthenium catalysts for alkaline membrane direct ethanol fuel cells

摘要

The activity of carbon supported palladium-based catalysts towards ethanol oxidation reaction in alkaline medium is investigated. To this end, Pd and PdxRu (x = 1, 6, 12) materials are synthesized supported on Vulcan XC72R by a modified impregnation method. These materials are characterized physicochemically and their composition varies between 40 and 50 wt. % of metal content. The mean size of nanoparticles is below 4 nm, and the size of the majority of particles ranges from 2 to 6 nm. The catalytic activity of these samples is also tested in half-cell and alkaline membrane direct ethanol fuel cell (AMDEFC). Lower onset potential and higher oxidation current densities is observed in palladium-rich bimetallic catalysts. By using the prepared samples as anode of AMDEFC and a commercial membrane of polybenzimidazole as solid electrolyte, the maximum power density is observed for Pd12Ru/C, 97 mW cm(-2), almost doubling the value achieved by the catalyst Pd/C (50 mW cm(-2)), and above the obtained by commercial PtRu/C catalyst (89 mW cm(-2)). (c) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.