Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1294637 | Journal of Power Sources | 2008 | 8 Pages |
Abstract
The present work aims at the investigation of Ln0.2Ce0.8O2âδ (where Ln = Sm, La, Gd) structural and electrical properties when in the Ln sub-lattice, Ba2+ and Sr2+ with ionic radii 1.42 and 1.26 Ã
, respectively, are introduced. The conductivity measurements were held both in air and in H2 + 3%H2O atmosphere using the 4-probe dc technique at the temperature range of 600-900 °C. Among all the samples, the highest value of electrical conductivity is obtained in the case of (Sm0.75Sr0.2Ba0.05)0.2Ce0.8O2âδ, both in air and in hydrogen atmosphere. In the case of H2 + 3%H2O the conductivity of the co-doped compounds increases in comparison with air. Moreover, the dependence of conductivity on the oxygen partial pressure, measured at the PO2 range of 0.21-10â22 atm, showed that the electrolytic area of alkaline-earth metals doped Ln0.2Ce0.8O2âδ is considerably enhanced, as predicted by the theory. Finally, by comparing the thermal expansion coefficients of the different materials (TEC), the thermo-mechanical compatibility between the co-doped and the other cell components was also investigated.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
E.Yu. Pikalova, V.I. Maragou, A.N. Demina, A.K. Demin, P.E. Tsiakaras,