Importance of Catalyst Stability vis-à-vis Hydrogen Peroxide Formation Rates in PEM Fuel Cell Electrodes

The role of catalyst stability on the adverse effects of hydrogen peroxide (H2O2) formation rates in a proton exchange membrane fuel cell (PEMFC) is investigated for Pt, Pt binary (PtX, X = Co, Ru, Rh, V, Ni) and ternary (PtCoX, X = Ir, Rh) catalysts. The selectivity of these catalysts towards H2O2...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2013-08
Main Authors: Sethuraman, Vijay A, Weidner, John W, Haug, Andrew T, Pemberton, Marianne, Protsailo, Lesia V
Format: Article
Language:English
Subjects:
Anode effect
Catalysis
Catalysts
Chemical reduction
Cobalt
Degradation
Durability
Electrodes
Fluorine
Fuel cells
Hydrogen peroxide
Ion concentration
Platinum
Proton exchange membrane fuel cells
Rhodium
Selectivity
Stability
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The role of catalyst stability on the adverse effects of hydrogen peroxide (H2O2) formation rates in a proton exchange membrane fuel cell (PEMFC) is investigated for Pt, Pt binary (PtX, X = Co, Ru, Rh, V, Ni) and ternary (PtCoX, X = Ir, Rh) catalysts. The selectivity of these catalysts towards H2O2 formation in the oxygen reduction reaction (ORR) was measured on a rotating ring disc electrode. These measured values were used in conjunction with local oxygen and proton concentrations to estimate local H2O2 formation rates in a PEMFC anode and cathode. The effect of H2O2 formation rates on the most active and durable of these catalysts (PtCo and PtIrCo) on Nafion membrane durability was studied using a single-sided membrane electrode assembly (MEA) with a built-in reference electrode. Fluoride ion concentration in the effluent water was used as an indicator of the membrane degradation rate. PtIrCo had the least fluorine emission rate (FER) followed by PtCo/KB and Pt/KB. Though PtCo and PtIrCo show higher selectivity for H2O2 formation than unalloyed Pt, they did not contribute to membrane degradation. This result is explained in terms of catalyst stability as measured in potential cycling tests in liquid electrolyte as well as in a functional PEM fuel cell.
ISSN:2331-8422
DOI:10.48550/arxiv.1308.4042