Open AccessEffect of Catalyst and Catalyst Layer Composition on Catalyst Support Durability
Author(s) -
Siddharth Komini Babu,
Rangachary Mukundan,
Chunmei Wang,
David A. Langlois,
David A. Cullen,
Dionissios D. Papadias,
Karren L. More,
Rajesh Ahluwalia,
Jim Waldecker,
Rodney L. Borup
Publication year - 2021
Publication title -
journal of the electrochemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.258
H-Index - 271
eISSN - 1945-7111
pISSN - 0013-4651
DOI - 10.1149/1945-7111/abf21f
Subject(s) - catalysis , durability , materials science , catalyst support , carbon fibers , proton exchange membrane fuel cell , chemical engineering , leaching (pedology) , catalyst poisoning , corrosion , electrolyte , composite material , chemistry , electrode , organic chemistry , environmental science , composite number , soil science , engineering , soil water
Polymer electrolyte membrane fuel cells (PEMFCs) are efficient, zero-emission engines for the automotive sector. However, cost and durability are major barriers for the commercialization of PEMFCs. Degradation of the carbon support in the cathode catalyst layer due to high potential excursions caused by unmitigated events like H 2 starvation, or start-up/shutdown are still a major durability issue in PEMFCs. Catalyst support durability was studied by accelerated stress tests (ASTs) that included repeated potential cycling from 1.0 to 1.5 V. The effect of catalyst layer composition on carbon corrosion was studied using membrane electrode assemblies with different catalysts (Pt, PtCo), catalyst composition (catalyst wt.%, supports), ionomer composition (loading, and equivalent weights). The corrosion of the carbon support is similar between Pt and PtCo catalysts. However, the performance degradation rate is higher for the alloy catalysts due to differences in catalyst particle size and the transition metal’s leaching accelerating the performance degradation. The carbon loss is lower for catalysts with lower initial carbon loading (or higher catalyst wt.%), which is better for durability. However, the cumulative loss of carbon is identical for electrodes with the same catalyst support irrespective of catalyst and ionomer composition in the catalyst layer.