含有octa-p-phenylene的自我组装分子树:从纳米晶体到纳米囊
Yong-Sik Yoo1, Jin-Ho Choi, Ji-Ho Song
1Center for Supramolecular Nano-Assembly and Department of Chemistry, Yonsei University, Shinchon 134, Seoul 120-749, Korea.
Journal of the American Chemical Society
|May 20, 2004
概括
树状分子根据头组大小自组成不同的纳米结构. 小头形成状结构,而较大的头根据溶剂条件产生3D超级晶体或空心纳米囊.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 树突和树突分子为自我组装提供独特的结构性质.
- 控制分子架构是设计新型纳米材料的关键.
研究的目的:
- 合成和表征具有不同灵活头部组的树状分子.
- 为了研究这些分子在溶液中的自我组装行为.
- 探索不同纳米结构的形成及其特性.
主要方法:
- 合成基于octa-p-phenylene的树状分子.
- 射线散射和传输电子显微镜 (TEM) 用于结构分析.
- 光学光谱学用于研究电子性质.
- 动态和静态光散射,扫描电子显微镜 (SEM) 用于聚合物表征.
主要成果:
- 具有小灵活头部的分子,自组装成状结构.
- 具有较大的头部的分子形成了离散的heptameric捆绑,组织成3D原始的或体超级晶体.
- 在选择性溶剂中,分子形成囊状的空洞聚合物.
- 层状和3D超晶体结构之间的光学特性有所不同.
结论:
- 树状分子可以形成具有平行排列的有组织的纳米晶体.
- 具有辐射排列的空心纳米囊也可以实现.
- 自组装结果可以根据分子设计 (头组大小) 和溶剂环境进行调整.
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