稀土氧化的阳离子和磁性排序,具有n=1的拉德尔斯登-波珀结构
Jhonatan R Guarín1, Carlos Frontera1, Judith Oró-Solé1
1Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain.
Chemistry of materials : a publication of the American Chemical Society
|June 3, 2024
概括
合成了具有Ruddlesden-Popper结构的新稀土过渡金属氧化. 这些新型化合物表现出多样化的晶体结构和磁性质,推进了材料科学.
科学领域:
- 固态化学 固态化学
- 材料科学是一种材料科学.
- 无机化学 无机化学 无机化学
背景情况:
- 稀土过渡金属氧化是一种新兴的材料类别,在催化和电子学中具有潜在的应用.
- 拉德尔斯登 - 波珀 (RP) 阶段的特点是它们的分层矿状结构,根据它们的组成和结构提供可调节的特性.
- 了解新RP阶段的合成,结构和特性对于开发先进的功能材料至关重要.
研究的目的:
- 为了合成和表征新的稀土过渡金属氧化化物,具有n=1的Ruddlesden-Popper结构.
- 为了研究这些新型化合物的离子静电学,晶体结构和磁性特性.
- 探索晶体结构,离子排序和磁性行为之间的关系.
主要方法:
- 金属化物和氧化物/氧化物在高温 (12001700°C) 的N2气体下发生固态反应.
- 同步射线X射线粉碎衍射和电子衍射用于晶体结构的确定.
- 中子粉衍射用于详细的离子排序分析.
- 磁化测量以探测磁性属性.
主要成果:
- 成功合成了具有n=1RP结构的新R2TaO4-xNx化合物 (R = La,Ce,Nd,Eu).
- 观察到正方体 (Pccn) 和四边形 (I41/acd) 晶体结构,其离子固态度不同.
- 中子衍射揭示了Ce2TaO1.19N2.81.81中的八面体内的特定排序.
- 在低温下,Ce和Eu化合物中观察到磁性排序,而Nd则保持偏磁性.
结论:
- 该研究介绍了第一个具有n=1 RP结构的稀土过渡金属氧化.
- 多样化的晶体结构和离子排序凸显了这些材料的可调性.
- 观察到的磁性特性与特定的稀土元素和晶体结构有关,为磁性材料设计提供了洞察力.
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