一些La(2/3-x) Li 3xTiO3氧化物的晶体结构和微观结构:电子衍射和显微镜和同步龙X射线衍射的互补使用的一个例子,用于研究复杂材料
Susana García-Martín1, Miguel A Alario-Franco, Helmut Ehrenberg
1Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense, 28040- Madrid, Spain.
Journal of the American Chemical Society
|March 18, 2004
概括
研究人员研究了La(2/3-x) Li(3x) TiO3氧化物,揭示了与矿相关的结构,倾斜的TiO6八面体. 这项工作完善了晶体结构模型,并解释了这些材料中复杂的微观结构.
科学领域:
- 固态化学 固态化学
- 材料科学是一种材料科学.
- 晶体学 晶体学是指结晶学.
背景情况:
- 氧化物是复杂的材料,具有潜在的应用.
- 了解它们的晶体结构和微观结构对于属性预测至关重要.
研究的目的:
- 为了阐明La(2/3-x) Li(3x) TiO3氧化物的晶体结构和微观结构.
- 提出一个精细的结构模型,考虑观察到的复杂性.
主要方法:
- 选择区域电子衍射 (SAED) 技术
- 高分辨率传输电子显微镜 (HRTEM) 的应用
- 粉末同步射线X射线衍射的粉末同步射线X射线
主要成果:
- 鉴定出一种与矿相关的结构,具有对角单元细胞 (√2ap x √2ap x 2ap),由TiO6八面体倾斜而产生的.
- 确定了La,Li ion的订单和空缺,以及Ti ion的排位.
- 域大小/形状和延伸缺陷,如应变和组成波动的特征.
结论:
- 该研究为La2/3-x) Li3x) TiO3氧化物提供了一个精细的结构模型.
- 拟议的模型成功地整合了观察到的复杂微观结构.
- 缺陷的详细描述为材料特性提供了洞察力.
相关概念视频
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