Projects per year
Abstract
In the past, platinum–copper catalysts have proven to be highly active for the oxygen reduction reaction (ORR), but transferring the high activities measured in thin-film rotating disk elec-trodes (TF-RDEs) to high-performing membrane electrode assemblies (MEAs) has proven diffi-cult due to stability issues during operation. High initial performance can be achieved. Howev-er, fast performance decay on a timescale of 24 h is induced by repeated voltage load steps with H2/air supplied. This performance decay is accelerated if high relative humidity (>60% RH) is set for a prolonged time and low voltages are applied during polarization. The reasons and possible solutions for this issue have been investigated by means of electrochemical impedance spec-troscopy and distribution of relaxation time analysis (EIS–DRT). The affected electrochemical sub-processes have been identified by comparing the PtCu electrocatalyst with commercial Pt/C benchmark materials in homemade catalyst-coated membranes (CCMs). The proton transport resistance (Rpt) increased by a factor of ~2 compared to the benchmark materials. These results provide important insight into the challenges encountered with the de-alloyed PtCu/KB elec-trocatalyst during cell break-in and operation. This provides a basis for improvements in the catalysts’ design and break-in procedures for the highly attractive PtCu/KB catalyst system.
Original language | English |
---|---|
Article number | 3544 |
Journal | Materials |
Volume | 16 |
Issue number | 9 |
DOIs | |
Publication status | Published - 5 May 2023 |
Keywords
- PEFC
- Catalyst layer
- platinum
- copper
- degradation
- ionomer
- EIS
- Membrane electrode assembly
- catalyst layer
- electrochemical impedance spectroscopy
- membrane electrode assembly
- platinum–copper
ASJC Scopus subject areas
- Condensed Matter Physics
- General Materials Science
Fields of Expertise
- Advanced Materials Science
- Mobility & Production
Fingerprint
Dive into the research topics of 'Mechanistic study of fast performance decay of Pt-Cu alloy based catalyst layers for polymer electrolyte fuel cells through electrochemical impedance spectroscopy'. Together they form a unique fingerprint.Projects
- 1 Finished
-
FC-Core - Fuel cell production - development of core competences
Hacker, V. (Co-Investigator (CoI)), Gollas, B. (Co-Investigator (CoI)), Marius, B. (Co-Investigator (CoI)), Mayer, K. (Co-Investigator (CoI)), Grandi, M. (Co-Investigator (CoI)) & Bock, S. (Co-Investigator (CoI))
1/01/21 → 31/03/23
Project: Research project