High-Resolution Mapping of the PFSA Polymer Distribution in PEFC Electrode Layers

Abstract

Perfluorosulfonic acid (PFSA) ionomer is a key component within electrode layers for the polymer electrolyte fuel cell (PEFC) since the solid electrolyte enables proton transport to the active catalyst site. Both the through-layer loading on a 100-nm length scale as well as the local film thickness distribution on a 1-nm scale of the ionomer in the porous layer structure are important to electrode performance so quantitative measurements of both properties are desired. In this paper, we present ionomer mapping measurements at both length scales using two common PEFC electrode constructions.

Imaging Reactivity of the Pt–Ionomer Interface in Fuel-Cell Catalyst Layers

“…The blended nanocomposite interface found inside PEMFC catalyst layers makes detailed structural analysis very complicated, even by advanced characterization techniques. − Conventional catalyst layers consist of a Pt/C catalyst, perfluorosulfonic acid (PFSA) polymer electrolyte (e.g., Nafion), and carbon support which are dispersed into an ink and spray painted into a porous film. The resulting 3D morphology is challenging to analyze.…”