Abstract
Studies of Ni-yttria-stabilized zirconia (YSZ) fuel electrode degradation mechanisms in solid oxide electrolysis cells (SOECs) are complicated by the different possible Ni-YSZ microstructures and compositions, and the variations in the H2/H2O ratio encountered in an electrolysis stack. Here we describe a life testing scheme aimed at providing survey results on degradation as a function of the H2O-H2 composition, with life tests carried out at five different steam contents from 90% to 10%. A Ni-YSZ-supported symmetric cell geometry is employed both with and without infiltrated nanoscale gadolinia-doped ceria (GDC). Impedance spectroscopy is utilized to observe changes in electrochemical characteristics during the life test, and a transmission-line-based equivalent circuit is used to model the data. Post-test electrode microstructures were observed. The results suggest that the GDC infiltrant reduces the electrode polarization resistance and provides more stable electrode polarization over a range of conditions.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 8363-8369 |
| Number of pages | 7 |
| Journal | Nano letters |
| Volume | 21 |
| Issue number | 19 |
| DOIs | |
| State | Published - Oct 13 2021 |
Funding
The authors gratefully acknowledge research support from the HydroGEN Advanced Water Splitting Materials Consortium, which was established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Fuel Cell Technologies Office, under award no. DE-0008079. The electrochemical modeling was in part supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP; no. 20213030030230).
Keywords
- degradation
- fuel electrode
- infiltration
- solid oxide electrolysis cell
ASJC Scopus subject areas
- Bioengineering
- General Chemistry
- General Materials Science
- Condensed Matter Physics
- Mechanical Engineering
