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DOE OSTI · 1827573

Probing Membrane Degradation with Varying Catalyst Layer Thickness and Carbon Support

Spears, André J.·Rockward, Tommy·Mukundan, Rangachary·Garzon, Fernando H.
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Abstract

Understanding membrane degradation continues to be of significant importance when studying fuel cell durability. Fuel cell performance and durability depends heavily on the membrane's chemical and mechanical integrity. In Nafion® membranes, hydroxyl radicals are the primary cause of chemical membrane degradation as they attack the membrane's polymer structure. Radical formation can ensue via peroxide decomposition at the cathode or gases reacting on Pt particles within the membrane. Here, a previous research effort on membrane degradation as a function of ultra-low Pt loadings (≤ 0.1 mgPt cm -2 ) showed the degradation rate increases with Pt loading. This is most likely due to more heterogenous sites for radical formation. Manufacturing MEAs with ultra-low Pt loadings can yield thin, non-uniform catalyst layers. In this research effort we studied membrane degradation with ultra-low Pt loadings while varying catalyst layer thickness, I/C ratio, and types of carbon support.

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25 ENERGY STORAGEEnergy SciencesPEFCdurabilitymembrane

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Spears, André J., Rockward, Tommy, Mukundan, Rangachary, Garzon, Fernando H.. 2020-09-23. Probing Membrane Degradation with Varying Catalyst Layer Thickness and Carbon Support. https://doi.org/10.1149/09809.0407ecst

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