探测C型双氧化物Th0.40Nd0.48Ce0.12O1.76,Th0.47Nd0.43Ce0.10O1.785和Th0.45Nd0.37Ce0.18O1.815的长距离和短距离结构化学作用,通过同步X射线衍射和吸收光谱镜
Gabriel L Murphy1, Elena Bazarkina2,3, Volodymyr Svitlyk4
1Institute of Energy and Climate Research (IEK-6), Forschungszentrum Jülich GmbH, Jülich 52428, Germany.
ACS omega
|July 1, 2024
概括
这项研究揭示了,和氧化化合物如何形成具有氧空缺的C型比克斯比特结构. Nd3+的结合导致局部键合并和晶格扩张,影响整体结构化学.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- C型比克斯拜特结构是具有潜在应用的复杂氧化物.
- 了解离子和氧空缺的相互作用对于材料设计至关重要.
- ,和氧化物为研究这些相互作用提供了一个独特的系统.
研究的目的:
- 系统地研究Th-Nd-Ce-O化合物的长距离和短距离结构化学.
- 阐明氧气空缺和离子结合在结构性质上的作用.
- 为了将局部化学行为与远程结构特征相关联.
主要方法:
- 同步射线X射线粉碎衍射 (S-PXRD) 用于远程结构.
- 高能分辨率光检测 边缘附近的X射线吸收 (HERFD-XANES) 对于Ce和Nd的氧化状态和局部协调.
- 扩展的X射线吸收细结构光谱 (EXAFS) 用于Th-O键距离.
- 电子结构计算以支持实验发现.
主要成果:
- 化合物形成C型比克斯比特结构,具有无序的离子和氧空缺.
- (Ce) 作为Ce4+存在,具有局部扭曲,而 (Nd) 作为Nd3+存在,促进电荷平衡和氧缺陷的形成.
- 增加的含量导致更短的Th-O和Th-Ce键长,局部键收缩,增强的Th离子价值,以及整体晶格扩张.
结论:
- 由Nd3+结合引起的氧缺陷显著影响局部键长和离子价值.
- 这项研究突出了不同的可变短程化学行为如何影响复杂氧化物的长程结构化学.
- 结果提供了对混合金属氧化物的结构性质关系的见解.
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