SEM and XAS characterization at beginning of life of Pd-based cathode electrocatalysts in PEM fuel cells
Författare
Summary, in English
The fuel cell performance of membrane electrode assemblies with a Pt anode and Pd, PdCu or Pd5Cu4Pt cathodes has been tested during 116 h (beginning of life). The incorporation of Cu to Pd increases the fuel cell performance. Incorporation of Pt leads to further improvement. SEM micrographs of the as-prepared and the fuel cell-tested assemblies show the effects of the 116 h of continuous operation. Nafion membranes were characterized by small angle X-ray scattering. The results show a reduction of the size of the lamellar domains in the perfluorinated matrix after fuel cell testing, but no correlation with the cathode electrocatalyst material. The cathode electrocatalysts were characterized by ex-situ synchrotron radiation X-ray diffraction and X-ray absorption spectroscopy at the Pd L-3, Cu K and Pt L-3 edges. Re-organization of Pd5Cu4Pt electrocatalyst after fuel cell testing was observed. The Cu in the electrocatalyst can be described as a nano-mixture of metallic Cu, alloyed Cu and CuO. The CuO acts as a promoter of the ORR. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Avdelning/ar
Publiceringsår
2014
Språk
Engelska
Sidor
5358-5370
Publikation/Tidskrift/Serie
International Journal of Hydrogen Energy
Volym
39
Issue
10
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Elsevier
Ämne
- Physical Sciences
- Atom and Molecular Physics and Optics
- Natural Sciences
Nyckelord
- Synchrotron radiation
- Electrocatalyst
- Fuel cell
- Pd nanoparticles
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1879-3487