Abstract
The present work aims for a comprehensive understanding of the degradation of proton exchange membrane water electrolyzer (PEMWE) with a low catalyst loading of 0.3 mg cm−2 Pt and 0.08 mg cm−2 Ir after a long-term test of 4500 h at 1.8 A cm−2. For the first time, the mechanism of cathode degradation is proposed using established physical models from two aspects: (1) Pt dissolution from nanoparticles and (2) Pt dissolution due to rapid Pt oxide reduction at the start of operation. As Ir dissolves and migrates through the membrane, Pt-Ir precipitates are formed in the membrane. Furthermore, iridium dissolution and subsequent re-deposition on the cathode constitute a major portion (42%) of the anode catalyst loss. The overall picture of degradation mechanisms and the distribution of platinum and iridium across the membrane electrode assembly (MEA) are provided.
| Original language | English |
|---|---|
| Article number | 118194 |
| Journal | Applied Catalysis B: Environmental |
| Volume | 260 |
| DOIs | |
| State | Published - Jan 2020 |
| Externally published | Yes |
Funding
The authors would like to thank the University of Connecticut for funding of the electron microscopy work and the U.S. Department of Energy (DE-SE0009213) for financial support on catalyst development and testing. The authors would like to thank Thermo Fisher Scientific-Center for Advanced Material and Microscopic Analysis for providing electron microscopes. The authors would like to thank Dr. Nemanja Danilovic and Dr. Christopher Capuano at Nel Hydrogen for MEA testing. The authors would like to thank Marcia Reid and Dr. Natalie Hamada at McMaster University for preparing the ultramicrotome specimen and TEM-EELS analysis. The authors would also like to thank Dr. C Barry Carter for the HRSTEM imaging of the Pt catalysts (Figs. 10 and S15). The authors would like to thank the University of Connecticut for funding of the electron microscopy work and the U.S. Department of Energy ( DE-SE0009213 ) for financial support on catalyst development and testing. The authors would like to thank Thermo Fisher Scientific-Center for Advanced Material and Microscopic Analysis for providing electron microscopes. The authors would like to thank Dr. Nemanja Danilovic and Dr. Christopher Capuano at Nel Hydrogen for MEA testing. The authors would like to thank Marcia Reid and Dr. Natalie Hamada at McMaster University for preparing the ultramicrotome specimen and TEM-EELS analysis. The authors would also like to thank Dr. C Barry Carter for the HRSTEM imaging of the Pt catalysts ( Figs. 10 and S15).
Keywords
- Degradation
- Membrane electrode assembly
- Proton exchange membrane water electrolysis
- Stability
