在化Pr2NiO4基混合导体中氧化离子的结构障碍和扩散途径
Masatomo Yashima1, Makiko Enoki, Takahiro Wakita
1Department of Materials Science and Engineering, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-Ku, Yokohama, Kanagawa 226-8502, Japan. yashima@materia.titech.ac.jp
Journal of the American Chemical Society
|February 9, 2008
概括
中子衍射揭示了K2NiF4结构混合导体中的曲的氧化物离子扩散路径. 这一发现对于理解先进陶材料中的离子运输至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- K2NiF4型氧化物是有前途的氧化物-离子和电子混合导体.
- 了解离子扩散机制对于它们在固体氧化物燃料电池和传感器中的应用至关重要.
研究的目的:
- 在特定的K2NiF4类型材料中研究氧化物离子扩散通路.
- 分析影响离子导电性的局部结构变化.
主要方法:
- 在位中子衍射在1015.6°C.
- 对MEM核密度的分析.
主要成果:
- 确定了一个曲线O2-O3-O2氧化物离子扩散路径的二维网络.
- 在 (Pr0.9La0.1) 2 (Ni0.74Cu0.21Ga0.05) O4+delta材料的 (Pr,La) -O层上观察到这些路径.
结论:
- 特定的晶体结构促进了异型氧化物离子扩散.
- 曲线扩散路径可能会影响这些混合导体的整体离子导电性.
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