Journal article
Concentration-dependent ionic conductivity and thermal stability of magnetron-sputtered nanocrystalline scandia-stabilized zirconia
Aarhus University1
Linköping University2
Thermo Ceramics, Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark3
Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark4
Risø National Laboratory for Sustainable Energy, Technical University of Denmark5
Electroceramics, Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark6
Nanocrystalline (nc) scandia-stabilized zirconia (SSZ) electrolytes with scandia contents of 5.9 to 15.9 mol% were synthesized by reactive magnetron sputtering. For scandia content ≥ 9.1 mol%, the as-deposited films were pure cubic phase with <111> texture, while traces of tetragonal phase was found for lower Sc content.
Single-line profile analysis of the 111 X-ray diffraction peak yielded an out-of-plane grain size of 10 nm and a microstrain of 2.0-2.2%, regardless of scandia content, for films deposited at 400 °C and a bias of -70 V. Films deposited at higher bias voltages showed a reduced grain size, yielding a grain size of 6 nm and a microstrain of 2.5% at -200 V and -250 V with additional incorporation of argon.
Temperature-dependent impedance spectroscopy of the SSZ films showed that the in-plane ionic conductivity had a maximum close to 10.7 mol% and decreased almost an order of magnitude as the scandia - content was increased to 15.9 mol%. The activation energy for oxygen ion migration was determined to be between 1.30 - 1.43 eV.
In addition, no dependence on grain size was observed. The above observations suggest a bulk mechanism for ionic conduction.
Language: | English |
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Year: | 2010 |
Pages: | 1140-1145 |
ISSN: | 18727689 and 01672738 |
Types: | Journal article |
DOI: | 10.1016/j.ssi.2010.06.010 |
ORCIDs: | Pryds, Nini and Bonanos, Nikolaos |
Impedance spectroscopy Physical vapor deposition SSZ X-ray diffraction