Thermal stability of Ba(Zr0.8-xCexY0.2)O2.9 ceramics in carbon dioxide.
- Resource Type
- Article
- Authors
- Tu, C.-S.; Chien, R. R.; Schmidt, V. H.; Lee, S.-C.; Huang, C.-C.; Tsai, C.-L.
- Source
- Journal of Applied Physics. May2009, Vol. 105 Issue 10, p103504-1-103504-7. 7p. 10 Graphs.
- Subject
- *X-ray diffraction
*CARBON dioxide
*ELECTRONIC ceramics
*BARIUM compounds
*RAMAN effect
*NONEQUILIBRIUM thermodynamics
- Language
- ISSN
- 0021-8979
In situ x-ray diffraction spectra (25-1000 °C) have been measured as a function of temperature for proton-conducting Ba(Zr0.8-xCexY0.2)O2.9 (x=0.0-0.4) ceramics in CO2 atmosphere. Atomic vibrations before and after exposure to CO2 were obtained by using the micro-Raman scattering (150-1600 cm-1). Ba(Zr0.8Y0.2)O2.9 and Ba(Zr0.6Ce0.2Y0.2)O2.9 reveal a promising thermal stability in CO2 without apparent decomposition up to 1000 °C. However, Ba(Zr0.5Ce0.3Y0.2)O2.9 and Ba(Zr0.4Ce0.4Y0.2)O2.9 exhibit thermally stable below 550 °C and then proceed an obvious chemical decomposition of BaCO3 and Zr0.8-xCexY0.2O2 above 550 °C, which were clearly evidenced by the Raman vibrations of 1057 and 466 cm-1, respectively. A first-order orthorhombic-hexagonal structure transition was confirmed in BaCO3 in the region of 810-850 °C upon heating. This study suggests that the Ba(Zr0.8-xCexY0.2)O2.9 ceramics with x¿0.2 are promising candidates for proton-conducting applications in CO2-containing environment. [ABSTRACT FROM AUTHOR]