Modeling Water Uptake and Pt Utilization in High Surface Area Carbon

Publication Type

Journal Article

Date Published

10/2019

Abstract

Local transport losses limit high-current density performance of fuel-cells, especially at low Pt-loadings. Optimizing catalyst-layer structure and material properties to mitigate these losses is critical for wide-scale fuel-cell commercialization. Carbon supports form the primary porous structure of catalyst layers in which Pt particles are deposited and ionomer films are distributed. Unlike non-porous carbon supports, high surface area carbon support is unique in its relative humidity dependent Pt utilization and performance due to presence of Pt particles in the micropores interior of carbon particles. We model water uptake and Pt utilization in catalyst layers with high-surface-area carbon support. Interactions between functional groups on the carbon pore walls and water play a vital role in controlling water uptake from water vapor by catalyst layers. Ionomer is shown to influence proton access in micropores, even though it may not deposit into the micropores.

Journal

ECS Transactions

Volume

92

Year of Publication

2019

Short Title

ECS Trans.

Refereed Designation

Refereed

Pagination

247 - 259

Issue

8

ISSN

1938-6737
Research Areas