有机多面体纳米晶体的受控形态生成从立方体,立方体到八面体,通过操纵生长动力学来控制生长动力学
Longtian Kang1, Hongbing Fu, Xinqiang Cao
1Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
Journal of the American Chemical Society
|January 20, 2011
概括
控制有机纳米晶体 (ONC) 形状是先进材料的关键. 这项研究使用了一种新的减少方法,通过控制生长动力学来精确调整ONC的大小和形态.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 结晶科学 结晶科学
背景情况:
- 有机纳米晶体 (ONC) 的形态控制对于特殊化学品和分子半导体的应用至关重要.
- 虽然热力学形状是可预测的,但ONC生长形态主要由不太了解的动力学因素决定.
研究的目的:
- 用一种新的还原合成方法研究有机纳米晶体 (ONC) 形态的动力控制.
- 探索像 cetyltrimethylammonium化物 (CTAB) 和聚乙烯 (PVP) 等封闭配体在影响 ONC 增长中的作用.
主要方法:
- 通过将四甲酸盐 (ZnTPP+ClO4-) 与酸盐 (Na+NO2-) 减少,合成了水四甲 (ZnTPP·H2O) ONC.
- 利用CTAB和PVP作为封闭配体来影响核和生长阶段.
- 通过控制ZnTPP·H2O构件的释放速度来操纵超和.
主要成果:
- 实现了构建块的受控释放,将核和生长阶段分开,以实现可调节的超和.
- CTAB充当了体稳定剂,而PVP选择性地附着在{020}s面上,显著改变了晶体的习惯.
- 成功生产了具有良好控制尺寸和形状的ONC,包括高超和度的热力学稳定八面体.
结论:
- 通过调整生长单元度和超和,展示了一种用于对ONC形态的动力控制的新方法.
- 展示了CTAB和PVP在指导ONC结晶中的不同角色.
- 突出了通过动力操纵实现所需的ONC形状的潜力,甚至是热力学稳定的形式.
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