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Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene
Published on: July 3, 2015
纳米晶体氧化铁气凝作为半孔磁性架构的磁气凝
Jeffrey W Long1, Michael S Logan, Christopher P Rhodes
1Surface Chemistry (Code 6170) and Materials and Sensors (Code 6360) Branches, Naval Research Laboratory, Washington, D.C. 20375, USA. jwlong@ccs.nrl.navy.mil
Journal of the American Chemical Society
|December 23, 2004
概括
我们创建了具有气凝特性的超偏磁氧化铁纳米架构. 这些材料提供可调节的磁相和可控制的孔结构,用于先进的应用.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 固态化学 固态化学
背景情况:
- 气凝具有独特的多孔结构和高表面积.
- 氧化铁纳米材料由于其磁性特性引起了人们的兴趣.
- 控制氧化铁的晶体阶段和纳米结构是一项挑战.
研究的目的:
- 开发具有超偏磁性行为的氧化铁晶体纳米架构.
- 为了保持理想的双连续孔固体网络和气凝的单体性质.
- 为了实现对孔-固体结构,纳米晶相和磁性属性的控制.
主要方法:
- 使用Fe (III) 盐和以环氧化物为基础的质子吸尘器生产无形氧化铁气凝的sol-gel方法.
- 控制温度和大气处理以将无形气凝转化为具有逆旋结构的纳米晶体形式.
- 使用电子显微镜,X射线和电子衍射,拉曼光谱和磁性分析进行表征.
主要成果:
- 开发了氧化铁的晶体纳米架构,表现出超对磁性行为.
- 成功保留了气凝的特征:高表面积 (>140 m2/g),通过连接的介质度 (2-50 nm) 和纳米级颗粒大小 (7-18 nm).
- 根据处理条件,可逆调节的纳米晶体形式主要表现出Fe(3) O(4) (磁铁) 或γ-Fe(2) O(3) (磁铁) 阶段.
结论:
- 建立了用于多功能纳米结构氧化铁材料的合成和加工协议.
- 证明了对孔-固体结构,纳米晶相和磁性属性的有效控制.
- 开发的材料结合了气凝特性与可调节的超对磁性.
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