Corrosion induced degradation of Pt/C model electrodes measured with electrochemical quartz crystal microbalance
Journal article, 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

Author

Björn Wickman

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Henrik Grönbeck

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Per Hanarp

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Bengt Herbert Kasemo

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics, Chemical Physics

Journal of the Electrochemical Society

0013-4651 (ISSN)

Vol. 157 4 B592-B598

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Roots

Basic sciences

Subject Categories

Atom and Molecular Physics and Optics

DOI

10.1149/1.3309730

More information

Created

10/7/2017