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Title: Catalyst-Layer Ionomer Imaging of Fuel Cells

 [1];  [1];  [1];  [1];  [1];  [2];  [2];  [3]
  1. French Atomic Energy Commission (CEA), Grenoble
  2. ORNL
  3. Los Alamos National Laboratory (LANL)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
OSTI Identifier:
DOE Contract Number:
Resource Type:
Resource Relation:
Journal Volume: 69; Journal Issue: 17; Conference: 228th ECS Meeting, San Francisco, CA, USA, 20151011, 20151011
Country of Publication:
United States

Citation Formats

Guetaz, Laure, Lopez-Haro, Miguel, Escribano, Sylvie, Morin, Arnaud, Gebel, Gerard, Cullen, David A, More, Karren Leslie, and Borup, Rod. Catalyst-Layer Ionomer Imaging of Fuel Cells. United States: N. p., 2015. Web. doi:10.1149/06917.0455ecst.
Guetaz, Laure, Lopez-Haro, Miguel, Escribano, Sylvie, Morin, Arnaud, Gebel, Gerard, Cullen, David A, More, Karren Leslie, & Borup, Rod. Catalyst-Layer Ionomer Imaging of Fuel Cells. United States. doi:10.1149/06917.0455ecst.
Guetaz, Laure, Lopez-Haro, Miguel, Escribano, Sylvie, Morin, Arnaud, Gebel, Gerard, Cullen, David A, More, Karren Leslie, and Borup, Rod. 2015. "Catalyst-Layer Ionomer Imaging of Fuel Cells". United States. doi:10.1149/06917.0455ecst.
title = {Catalyst-Layer Ionomer Imaging of Fuel Cells},
author = {Guetaz, Laure and Lopez-Haro, Miguel and Escribano, Sylvie and Morin, Arnaud and Gebel, Gerard and Cullen, David A and More, Karren Leslie and Borup, Rod},
abstractNote = {},
doi = {10.1149/06917.0455ecst},
journal = {},
number = 17,
volume = 69,
place = {United States},
year = 2015,
month = 1

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  • Investigation of membrane/electrode assembly (MEA) microstructure has become an essential step to optimize the MEA components and manufacturing processes or to study the MEA degradation. For these investigations, transmission electron microscopy (TEM) is a tool of choice as it provides direct imaging of the different components. TEM is then widely used for analyzing the catalyst nanoparticles and their carbon support. However, the ionomer inside the electrode is more difficult to be imaged. The difficulties come from the fact that the ionomer forms an ultrathin layer surrounding the carbon particles and in addition, these two components, having similar density, present nomore » difference in contrast. In this paper, we show how the recent progresses in TEM techniques as spherical aberration (Cs) corrected HRTEM, electron tomography and X-EDS elemental mapping provide new possibilities for imaging this ionomer network and consequently to study its degradation.« less
  • Effects of a perfluorosulfonate ionomer (PFSI) and of a polytetrafluoroethylene (PTFE) loaded carbon (PTFE-C) on the catalyst layer in the electrode of a polymer electrolyte fuel cell (PEFC) prepared by a new method based on the process of PFSI-colloid formation were investigated by electrochemical techniques and a mercury pore sizer. The microstructure of the catalyst layer and its effect on the PEFC performance were affected by the contents of both PFSI and PTFE-C. The catalyst layer has two distinctive pore distributions with a boundary of ca. 0.04 {micro}m. The volume of larger pore (secondary pore) decreased with an increase ofmore » the PFSI content and increased with an increase of the PTFE-C content. The volume of the smaller pore (primary pore) was independent of the content of both PFSI and PTFE-C. The PFSI as well as the PTFE existed only in the secondary pore. The content of PFSI affected the performance of PEFC in the whole current density range. On the other hand, the content of PTFE-C influenced it greatly at high current density due to its gas feeding faculty. In the PEFC, reaction sites were found to exist in the secondary pore coated with the macromolecule PFSI. The hydrophobic PTFE-C works to supply the reaction gas to the reaction sites covered with the PFSI in the secondary pore, and to exhaust the product water from there. The high performance of PEFC at high current density was achieved with the best mixture of the PFSI and the PTFE-C.« less
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