Corrosion induced degradation of Pt/C model electrodes measured with electrochemical quartz crystal microbalance
Artikel i vetenskaplig tidskrift, 2010

Degradation of fuel cell model electrodes during accelerated aging was studied using electrochemical quartz crystal microbalance with dissipation monitoring. The model electrodes, consisting of Pt particles (5 nm) on planar carbon and Pt-only and carbon-only films, were prepared by thermal evaporation onto uncoated quartz crystal sensors. The characterization of electrode composition and morphology was performed by X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, and atomic force microscopy. The experiments were conducted in a flow cell with 0.5 M H(2)SO(4) at room temperature and up to 70 degrees C by repeated cycling between 0.02 and 1.4 V(RHE) (where RHE is reversible hydrogen electrode) at 50 mV s(-1). During cyclic corrosion, the Pt-only sample loses mass equivalent to 0.6% of a monolayer per cycle in a process that is not temperature-dependent. The experiments with the Pt particle layer on a carbon electrode show a mass loss that is almost 2 times larger than the Pt-only sample and exhibits an Arrhenius type of temperature dependence. The results suggest that the presence of Pt catalyzes carbon corrosion with an apparent activation energy of 0.33 eV. In all measurements, the carbon-only sample loses much less mass than the other samples.

Polymer Electrolyte Fuel Cell

PEMFC

electrode degradation

EQCM

Pt dissolution

Carbon corrosion

electrochemical quartz crystal microbalance

Författare

Björn Wickman

Kompetenscentrum katalys (KCK)

Chalmers, Teknisk fysik, Kemisk fysik

Henrik Grönbeck

Kompetenscentrum katalys (KCK)

Chalmers, Teknisk fysik, Kemisk fysik

Per Hanarp

Kompetenscentrum katalys (KCK)

Chalmers, Teknisk fysik, Kemisk fysik

Bengt Herbert Kasemo

Kompetenscentrum katalys (KCK)

Chalmers, Teknisk fysik, Kemisk fysik

Journal of the Electrochemical Society

0013-4651 (ISSN)

Vol. 157 4 B592-B598

Styrkeområden

Nanovetenskap och nanoteknik

Transport

Energi

Materialvetenskap

Fundament

Grundläggande vetenskaper

Ämneskategorier

Atom- och molekylfysik och optik

DOI

10.1149/1.3309730

Mer information

Skapat

2017-10-07