Abstract
We report the synthesis, structure, microstructure, chemical stability in H2O and CO2, and electrical transport properties of an oxide ion-conducting perovskite-related structure Ba3In2MO8 (M = Zr, Ce, Zr0.5Ce0.5). Powder X-ray diffraction confirmed the formation of a simple cubic perovskite-like structure for Ba3In2ZrO8 (a = 4.205(9) Å), Ba3In2CeO8 (a = 4.234(1) Å), and Ba3In2Zr0.5Ce0.5O8 (a = 4.285(8) Å). The increase in lattice constant is consistent with the Shannon's ionic radius trend. Among the three samples investigated, Ba3In2ZrO8 was found to be stable against reaction with pure CO2 at elevated temperature, while the Ce and 1:1 Zr and Ce compounds were unstable at 600 °C. Ba3In2ZrO8, Ba3In2CeO8, and Ba3In2Zr0.5Ce0.5O8 were found to be chemically unstable in H2O at about 50 °C. The bulk electrical conductivity of the samples prepared at different temperatures was found to be nearly the same; the total conductivity (bulk + grain-boundary + electrode) seems to change with sintering temperature. Both Ba3In2ZrO8 and Ba3In2CeO8, prepared at 1,400 °C, exhibited comparable electrical conductivity of about 6×10-3 S cm-1 at 800 °C, which is comparable to that of conventional Y2O3-doped ZrO2 electrolyte. These compounds are very promising electroltes, provided that their chemical and mechnical stabitities are improved without losing any ionic conductivity.
Original language | English |
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Pages (from-to) | 581-589 |
Number of pages | 9 |
Journal | Ionics |
Volume | 16 |
Issue number | 7 |
DOIs | |
Publication status | Published - 2010 |
Keywords
- AC conductivities
- AC impedance
- Anionic conductors
- BaInZrCexO (x = 0, 0.5, 1)
- Chemical stability
- Ionic conductivities
- Oxide electrolytes
- Perovskites