Comparison of modeling and experimental results of modified Pt-​based PEMFC cathode-​catalysts

A4 Konferenspublikationer


Interna författare/redaktörer


Publikationens författare: Puhakka Eini, Koponen Ulla, Bergelin Mikael, Keskinen Jari, Kumpulainen Heikki, Peltonen Terttu, Valkiainen Matti
Redaktörer: Murthy, Fuller, Van Zee, Gottesfeld
Publiceringsår: 2005
Förläggare: The Electrochemical Society
Moderpublikationens namn: Proton Conducting Membrane Fuel Cells III : proceedings of the International Symposium
Volym: 2002-31
Artikelns första sida, sidnummer: 74
Artikelns sista sida, sidnummer: 88
ISBN: 9781566774551


Abstrakt

Pt-​based binary and ternary alloy catalysts were investigated by modeling methods and exptl. The lattice parameters of Pt, Pt3Cr, Pt3Co, Pt3Ir, Pt2CoCr, Pt2CoIr, Pt2Cr2 and Pt2Co2 were detd. by mol. modeling methods. According to the optimized structures, the most typical crystal faces were generated. In order to get a good description of steric and electrostatic factors of material surfaces, reconstruction of surface atoms was taken into account. It was shown that the alloying of Pt with base metals affect surface charge densities, which enables steering of surface reactions into desired positions on the catalyst surface. Both com. (E-​TEK) and lab.-​made catalyst powders and inks based on Pt:Co​/C and Pt:Co:Cr​/C were characterized voltammetrically. The active Pt surface area increased after activating the catalyst. This can most likely be attributed to the dissolving of Co and Cr from the alloys. All lab.-​made catalysts were also characterized by XRD, TEM and STEM​/EDS.

Senast uppdaterad 2020-02-04 vid 09:19