Abstract
The present work reports estimates for the hole conductivity of lanthanum gallate-based samples (La0.9Sr0.1Ga1-x FexO3-sigma, with x = 0 and x = 0.2), in the range 700-1000 degrees C. These estimates were based on electrochemical permeability measurements, and were compared to previous estimates obtained from ion-blocking measurements. The p-type conductivity of these materials was confirmed to be strongly influenced by the content of Fe. The activation energy for p-type conductivity was found to be in the range 0.9-1 eV, lower than usually observed for alternative electrolytes based in zirconia or ceria. The increase in p-type conductivity with Fe content can be explained by a relatively easy formation of Fe4+ ions under oxidizing conditions, a basic requirement for the establishment of a small polaron-type conduction mechanism. (C) 2000 Elsevier Science Ltd. All rights reserved.
Original language | English |
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Pages (from-to) | 2095-2099 |
Number of pages | 5 |
Journal | Electrochimica Acta |
Volume | 45 |
Issue number | 13 |
Publication status | Published - 2000 |
Keywords
- lanthanum gallate
- p-type conductivity
- electrochemical permeability
- electronic conductivity
- mixed conductors
- PEROVSKITE-TYPE OXIDE
- CONDUCTIVITY
- ELECTROLYTE
- LAFEO3
- CELLS
- FE