Exploring substrate/ionomer interaction under oxidizing and reducing environments

Exploring substrate/ionomer interaction under oxidizing and reducing environments

TitleExploring substrate/ionomer interaction under oxidizing and reducing environments
Publication TypeJournal Article
Year of Publication2018
AuthorsMeron Tesfaye, Andrew N MacDonald, Peter J Dudenas, Ahmet Kusoglu, Adam Z Weber
JournalElectrochemistry Communications
Volume87
Pagination86 - 90
Date Published01/2018
ISSN13882481
Keywordsadsorption, catalyst layers, confinement, fuel cell, Hydrogen, ionomer thin-film, membrane fuel-cells, morphology, nafion thin-films, native-oxide, oxidation, oxygen reduction, platinum, platinum interface, surface
Abstract

Local gas transport limitation attributed to the ionomer thin-film in the catalyst layer is a major deterrent to widespread commercialization of polymer-electrolyte fuel cells. So far functionality and limitations of these thin-films have been assumed identical in the anode and cathode. In this study, Nafion ionomer thin-films on platinum(Pt) support were exposed to H2 and air as model schemes, mimicking anode and cathode catalyst layers. Findings indicate decreased swelling, increased densification of ionomer matrix, and increased humidity-induced aging rates in reducing environment, compared to oxidizing and inert environments. Observed phenomenon could be related to underlying Pt-gas interaction dictating Pt-ionomer behavior. Presented results could have significant implications about the disparate behavior of ionomer thin-film in anode and cathode catalyst layers.

DOI10.1016/j.elecom.2018.01.004
Short TitleElectrochemistry Communications
Refereed DesignationRefereed