从平均到局部结构:瑞特维尔德和原子对分布函数 (PDF) 对团在石-NdYY中的研究
A M Milinda Abeykoon1, Wolfgang Donner, Michela Brunelli
1Department of Physics, University of Houston, Houston, Texas 77204, USA. aabeykoon@uh.edu
Journal of the American Chemical Society
|September 3, 2009
概括
研究人员确定了 (Se) 纳米颗粒在石NdY中的结构. 他们观察了20个Se原子的纳米集群,揭示了详细的集群内部和集群框架相关性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 固态化学 固态化学
背景情况:
- 石是微孔的晶体酸,被广泛用作催化剂和吸附剂.
- 控制热带石框架内的纳米粒子形成对于先进的材料特性至关重要.
- (Se) 纳米粒子表现出与各种应用相关的独特电子和光学特性.
研究的目的:
- 为了阐明精确的纳米颗粒的原子结构被限制在化 NdY 的alpha-cages.
- 了解纳米集群与热带石框架之间的相关性.
- 为了研究在X射线衍射数据中观察到的扩散散射的起源.
主要方法:
- 采集X射线衍射 (XRD) 数据.
- 瑞特维尔德精炼用于平均晶体结构的确定.
- 对于局部原子结构和相关性的对分布函数 (PDF) 分析.
主要成果:
- 随着的加入,二氧化 NdY 框架保持不变.
- 平均结构显示了由大约20个原子组成的纳米集群.
- 分散散射归因于集群内部和集群框架相关性,通过PDF分析成功建模.
结论:
- 该研究成功确定了 NdY. zeolite 内的纳米粒子的结构.
- 形成了具有特定原子性和相关性的离散纳米集群.
- PDF分析是描述纳米粒子结构及其在多孔材料中的相互作用的强大工具.
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