多核固态NMR光谱对合化纳米粒子的多核固态NMR光谱
Andy Y H Lo1, Vasanthakumaran Sudarsan, Sri Sivakumar
1Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4.
Journal of the American Chemical Society
|March 28, 2007
概括
这项研究使用固态NMR和XRD来表征兰化物合的LaF3纳米粒子. 结果显示,核心结构被保留,表面修改和均的剂分布.
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:
- 甲 (LaF3) 纳米粒子 (NP) 在各种应用中至关重要.
- 了解化NP的结构完整性和表面化学是优化其性能至关重要的.
- 描述兰他尼德兴奋剂对LaF3 NP结构和连接体相互作用的影响是关键.
研究的目的:
- 为了全面描述纯粹的和化物合的LaF3纳米粒子 (NP) 及其相应的散装材料.
- 调查Laf3核心在兴奋剂和NP形成时的结构保留.
- 为了阐明在NP表面上封闭连接体相互作用的性质.
主要方法:
- 多核固态核磁共振 (NMR) 光谱 (139La, 19F, 45Sc, 1H, 31P). 多核固态核磁共振 (NMR) 光谱 (139La, 19F, 45Sc, 1H, 31P).
- 粉末X射线衍射 (XRD). 粉末X射线衍射.
- 魔法角旋转 (MAS) 的NMR和交叉极化 (CP) /MAS的NMR技术.
主要成果:
- 固态NMR和XRD证实了LaF3结构在NP中保持在分子水平.
- 在NMR光谱中不均的扩展表明了从NP核心到表面的La和F环境的梯度.
- 兰他尼德兴奋剂 (5-10mol%) 并没有显著改变NP核心结构,而兴奋剂分布均.
- 连接体分析揭示了NP表面的dithiophosphate,thiophosphate和phosphate物种,证实了连接体协调.
结论:
- 拉菲3纳米粒子保留了其核心结构,但表现出影响当地环境的表面修饰.
- 兰他尼德补充剂集成到LaF3网格部位中,在NP核心中均分布.
- -n-octadectyldithiophosphate连接物与NP表面协调,有证据表明连接物降解产物.
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