Overcoming Artifacts in Imaging Nanometer-thick Ionomer Layers in Anion Exchange Membrane Fuel Cells

Abstract

A major focus of anion exchange membrane fuel cell (AEMFC) research revolves around the study of the performance and degradation of the catalyst layer structure [1]. This complex structure typically consists of catalyst nanoparticles, such as platinum, loaded onto a carbon support along with a dispersion of polymeric ionomer. The interactions between the catalyst-loaded carbon particles and the ionomer have a direct impact on both the ionic and electronic conductivity in the catalyst layer [2,3]. A robust approach to characterize the distribution of ionomer in the catalyst layer is therefore important to advance our understanding of fuel cell performance. Here, we show that low-dose cryo-TEM imaging enables direct imaging of the ionomer and its distribution in the catalyst layer of AEMFCs.

Opportunities of Ionomer Development for Anion-Exchange Membrane Water Electrolysis

“…Mayerhofer, Thiele et al visualized distinct polymer aggregates in CLs for high Aemion binder contents (>10 wt % with IrO 2 ). 103 To resolve nanometer sized domains of ionomer, techniques such as cryogenic TEM might be used, 104 although analysis at this scale sacrifices understanding how ionomer is distributed throughout the entire CL.…”