通过化物尺寸灵活性实现的LnHO中化学压力诱导的阳离子顺序-乱序过渡
Hiroki Yamashita1, Thibault Broux1, Yoji Kobayashi1
1Graduate School of Engineering , Kyoto University , Kyoto 615-8510 , Japan.
Journal of the American Chemical Society
|August 22, 2018
概括
研究人员在兰化氧化物中发现了离子顺序-乱序过渡. 这一发现对于涉及化物扩散的应用,如催化和固态电化学装置至关重要.
科学领域:
- 固态化学
- 材料科学
- 无机化学
背景情况:
- 在材料科学中,阴离子顺序-乱序过渡已经得到了很好的证实.
- 呈现类似过渡的离子类型相对罕见.
- 兰化氧化 (LnHO) 为研究阴离子行为提供了一个潜在的平台.
研究的目的:
- 合成和表征新的兰化氧化物.
- 调查离子秩序-混乱转变的发生和驱动力.
- 探索兰他尼德离子大小和结构排列之间的关系.
主要方法:
- 化氧化的合成 (Ln = Sm,Gd,Tb,Dy,Ho,Er).
- 用X射线衍射进行结构分析.
- 对离子结合和协调环境的分析.
主要成果:
- 将已知的LnHO系列扩展到包括Sm,Gd,Tb,Dy,Ho和Er.
- 观察到从离子有序 (P4/nmm) 转变为无序 (Fm3̅m) 结构,其离子半径减少.
- 在无序阶段确定了氧化物离子的低结合作为排序的驱动因素.
- 证明了化物离子尺寸灵活性在转变中的作用.
结论:
- 在兰化氧化物中可以实现离子顺序-乱序过渡.
- 这种转变是由离子大小和离子结合之间的相互作用驱动的.
- 控制这些材料的离子排序对于化物扩散,催化和电化学装置的应用至关重要.
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