Chemical Expansion and Change in Lattice Constant of Y‐Doped BaZrO 3 by Hydration/Dehydration Reaction and Final Heat‐Treating Temperature

• Published in: Journal of the American Ceramic Society Vol. 96; no. 3; pp. 879 - 884
• Main Authors: Hiraiwa, Chihiro, Han, Donglin, Kuramitsu, Akiko, Kuwabara, Akihide, Takeuchi, Hisao, Majima, Masatoshi, Uda, Tetsuya
• Format: Journal Article
• Language: English
• Published: 01.03.2013
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/jace.12172

Knowledge of thermal behavior of electrolyte is important for fuel cell fabrication. In this study, using high‐temperature X ‐ray diffraction analysis ( HT ‐ XRD ) and thermo‐mechanical analysis ( TMA ), a systematic investigation of lattice constants was performed on Y‐doped BaZrO 3 , which is a promising candidate for electrolyte in protonic ceramic fuel cells. The results revealed that a chemical expansion was observed between 300°C and 450°C during the heating process in HT ‐ XRD , and was attributed to the dehydration of BZY . Furthermore, it was found that the lattice constants of the samples doped with Y, Sm, Eu, and Dy were larger for the ones finally heat‐treated at 1600°C for sintering than those heat‐treated at 1300°C for synthesizing. The similar behavior was not observed in Sc‐doped samples.