从古巴型Fe-S集群中合成磁铁硫化物纳米晶体的相控
1School of Chemistry and School of Materials, The University of Manchester, Oxford Road, Manchester M139PL, UK.
Journal of the American Chemical Society
|November 28, 2008
概括
磁铁硫化物纳米晶体合成中的相位控制是使用单源前体实现的. 温度决定了铁硫化物纳米晶体的形成,这些铁硫化物纳米晶体都表现出超对磁性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 无机化学 无机化学 有机化学
背景情况:
- 控制磁铁硫化物纳米晶体的相位和大小对于它们的应用至关重要.
- 现有的合成方法往往缺乏对纳米晶体组成和结构的精确控制.
- 单一来源的前体为控制的纳米材料合成提供了一个有前途的途径.
研究的目的:
- 在合成磁铁硫化物纳米晶体期间实现相位控制.
- 研究温度对纳米晶体组成,结构和尺寸的影响.
- 为了探索合成的硫化铁纳米晶体的磁性特性.
主要方法:
- 使用古巴类型的Fe-S集群,bis ((tetra-n-butylammonium) tetrakis[benezenethiolato-mu3-sulfido-iron],作为一个单一来源的前体.
- 在不同温度下将前体分解为基胺,以合成纳米晶体.
- 描述了由此产生的纳米晶体的组成,结构和尺寸.
主要成果:
- 成功合成了具有控制相位的磁铁硫化物纳米晶体.
- 低温产生了矿 (Fe7S8) 纳米晶体 (平均直径5.6纳米).
- 较高的温度产生了可调节的灰岩石 (Fe3S4) 纳米晶体 (2.5-4.5 nm).
- 所有合成的纳米晶体在室温下都表现出超偏磁性行为.
结论:
- 一个单一来源的前体使得硫化铁纳米晶合成中的精确相位控制成为可能.
- 温度是调整硫化铁纳米晶体相位,结构和大小的关键参数.
- 合成的硫化铁纳米晶体具有可调节的磁性,适合各种应用.
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