室温阻塞磁纳米颗粒 基于费里特 通过三步热分解过程促进
Kevin Sartori1,2, Fadi Choueikani2, Alexandre Gloter3
1Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 , F-67000 Strasbourg , France.
Journal of the American Chemical Society
|June 1, 2019
概括
具有洋型结构的稀土无磁纳米粒子具有增强的磁性异构性. 这些以氧化铁为基础的16nm纳米粒子在室温下被阻,显示出永久磁体应用的前景.
科学领域:
- 材料科学
- 纳米技术
- 磁性
背景情况:
- 结合硬和软磁相的交换合纳米粒子提供了增强的磁性异构性.
- 在20nm以下的无稀土铁磁纳米颗粒中实现室温阻塞仍然是简单的核心外结构的挑战.
研究的目的:
- 开发具有增强磁性特性的新型洋型磁性纳米粒子.
- 调查稀土无纳米颗粒中室温阻塞的可能性.
主要方法:
- 使用基于热分解的三步种子中介生长方法.
- 具有氧化铁核心,化铁中间和外氧化铁的制造芯@贝@贝纳米粒子.
主要成果:
- 已经成功合成了16纳米的磁性纳米粒子.
- 由于在核心@shell和shell@shell接口上的双交换合,显著增加了磁性异构能量.
- 在这些基于氧化铁的纳米粒子中实现了室温阻塞.
结论:
- 洋类型的磁纳米粒子结构有效增强磁性异构性,并使室温阻断成为可能.
- 这些发现对开发先进的无稀土永久磁铁非常有希望.
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