Water Uptake in PEMFC Catalyst Layers

Date Published
10/2011
Publication Type
Conference Paper
Authors
DOI
10.1149/1.3635598
LBL Report Number
LBNL-5322E
Abstract

Water uptake profiles of proton-exchange-membrane fuel-cell catalyst layers are characterized in the form of capillary-pressure saturation (Pc-S) curves. The curves indicate that the catalyst layers tested are highly hydrophilic and require capillary pressures as low as -80 kPa to eject imbibed water. Comparison of materials made with and without Pt indicates a difference in water ejection and uptake phenomena due to the presence of Pt. The addition of Pt increases the tendency of the catalyst layer to retain water. Dynamic vapor sorption (DVS) is used to characterize the water-vapor sorption onto Nafion, Pt/C, and C surfaces. The DVS results align with the trends found from the Pc-S curves and show an increased propensity for water uptake in the presence of Pt. The effect of the ion in Nafion, sodium or protonated form, is also compared and demonstrates that although the protonation of the Nafion in the catalyst layer also increases hydrophilicity, the effect is not as great as that caused by Pt.

Notes

LBNL-5322E

Conference Name
220th ECS Meeting
Volume
41
Year of Publication
2011
Number
1
Pagination
647
Publisher
ECS
Conference Location
Boston, MA
Refereed Designation
Unknown
Organizations
Research Areas
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