Experimentally validated model for CO oxidation on PtRu/C in a porous PEFC electrode
2005 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, Vol. 152, no 1, A23-A31 p.Article in journal (Refereed) Published
Carbon monoxide oxidation in a porous polymer electrolyte fuel cell (PEFC) electrode with PtRu/C catalyst was studied with steady-state polarization curves and open- circuit decay measurements. The Tafel slope was about 210 mV/decade and the reaction order for CO was about 0.45 at 0.4 V vs. RHE. This experimental behavior is explained with a mathematical model with CO adsorbing on Pt and water adsorbing on Ru. Kinetic parameters are determined from a fitting of the model to both the steady-state and the transient measurements. A single rate-determining step cannot account for the polarization curves over the whole potential range. At mid-range potentials the oxidation step is rate-determining but at lower potentials the water adsorption might be rate-determining. The open- circuit decay measurements gave noise-free measurements and confirmed the accuracy of the steady-state measurements. The obtained model for CO oxidation where the coverage of COads on Pt is determined can be used together with a model for H-2 oxidation.
Place, publisher, year, edition, pages
2005. Vol. 152, no 1, A23-A31 p.
membrane fuel-cells, overpotential decay behavior, mass-transport limitations, rotating-disk electrode, pt-ru, chlorine evolution, electrooxidation, h-2, adsorption, electrocatalysis
IdentifiersURN: urn:nbn:se:kth:diva-14436DOI: 10.1149/1.1825378ISI: 000225864900005ScopusID: 2-s2.0-12744255074OAI: oai:DiVA.org:kth-14436DiVA: diva2:332477
QC 201005252010-08-052010-08-05Bibliographically approved