在 NaCl 型 FePt-MnO 双纳米晶超晶格中增强了热稳定性和磁性特性
Angang Dong1, Jun Chen, Xingchen Ye
1The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States. adong@lbl.gov
Journal of the American Chemical Society
|August 2, 2011
概括
我们使用铁和氧化物纳米晶体制造了二元纳米晶体超级晶体. 这种方法可以防止在相位转换过程中铁纳米粒子烧结,从而使有序铁磁阵列用于数据存储.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 磁力学 磁力学 是一种
背景情况:
- 铁 (FePt) 纳米粒子由于其硬磁性特性,对高密度数据存储具有前景.
- 将FePt纳米粒子转换为L1(0) 阶段往往会导致烧结,降低它们的有序结构.
- 开发在相位转换过程中保持纳米粒子秩序的方法对于应用至关重要.
研究的目的:
- 开发一种制造有序FePt基纳米晶超的方法.
- 研究与其他纳米晶体联合组装对FePt相位转换的影响.
- 为了能够创建稳定,有序的铁磁纳米晶阵列用于数据存储.
主要方法:
- 铁 (FePt) 和氧化 (MnO) 纳米晶体在液体-空气界面的联合组装,形成二元超级晶格膜.
- 在650°C时对二进制超级网进行热,将FePt转换为L1(0) 阶段.
- 对化二进制超网与只有FePt的超网和无序混合物的比较分析.
主要成果:
- 成功地生长了NaCl类型的二进制纳米晶超.
- 在二进制超级网格内实现FePtNCs转换为L1(0) 阶段,而不会降低远程顺序.
- 在相同的回火条件下观察到在FePt-only超级格子和无序混合物中显著的FePt烧结.
- 证明联合组装可以防止FePt在L1(0) 阶段转换过程中的烧结.
结论:
- 将FePtNCs纳入二进制超级网格有效地防止在转换到硬磁性L1(0) 阶段期间的烧结.
- 这种方法为制造有序铁磁纳米晶阵列提供了新的途径.
- 开发的方法对高密度数据存储应用有前途.
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