Abstract
Temperature induced degradation in Solid Oxide Fuel Cell (SOFC) Ni-YSZ anodes was studied using both impedance spectroscopy and three-dimensional tomography via Focused Ion Beam-Scanning Electron Microscopy. A 100 h anneal at 1100 °C caused a 90% increase in cell polarization resistance, which correlated with the observed factor of ∼2 reduction in the electrochemically active three-phase boundary (TPB) density. The TPB decrease was caused by a significant decrease in pore percolation, and a reduction in pore interfacial area due to pores becoming larger and more equiaxed. The anneal caused no measurable change in average Ni particle size; Ni coarsening was apparently highly constrained in these anodes due to the relatively large YSZ volume fraction and low pore volume.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2640-2643 |
| Number of pages | 4 |
| Journal | Journal of Power Sources |
| Volume | 196 |
| Issue number | 5 |
| DOIs | |
| State | Published - Mar 1 2011 |
Funding
The authors gratefully acknowledge the financial support from the National Science Foundation Ceramics program through Grant DMR-0907639 . The FIB-SEM was accomplished at the Electron Microscopy Center for Materials Research at Argonne National Laboratory, a US Department of Energy Office of Science Laboratory operated under Contract No. DE-AC02-06CH11357 by UChicago Argonne, LLC. Graduate student Kyle Yakal-Kremksi and undergraduate students Zach Patterson and Danni Jin are acknowledged for their help with manual segmentation required for some images. The authors also thank Hsun-Yi Chen and Prof. Katsuyo Thornton at the University of Michigan for the tortuosity calculations.
Keywords
- 3D
- Degradation
- FIB-SEM
- Microstructure
- Ni-YSZ
- SOFC
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering
