来自晶体的空隙和黄,覆盖粒子
Melinda Sindoro1, Steve Granick
1Department of Chemistry, ‡Department of Materials Science and Engineering, and §Department of Physics, University of Illinois , Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|September 23, 2014
概括
几何挫折导致粒子上的ZIF-8外从连续结构转变为黄皮外结构. 局部表面曲率决定了这种转变,为核心外材料提供了一个新的设计规则.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 晶体学 晶体学是指结晶学.
背景情况:
- 聚晶外的焦化物伊米达酸框架 (ZIF-8) 协调聚合物是在体大小的颗粒上生长的.
- 了解这些核心结构的形态演变对于它们的应用至关重要.
研究的目的:
- 调查ZIF-8.8中核心外形态的曲率驱动的形成.
- 阐明从连续结构转变为没有模板或蚀刻的黄皮结构背后的机制.
- 建立基于局部表面曲率的设计规则,以控制外形态.
主要方法:
- ZIF-8贝在各种血核颗粒 (立方体,棒状,花生状) 上的生长.
- 使用显微镜技术 (隐含) 来对由此产生的核心外结构进行形态分析.
- 贝形态与核心粒子局部表面曲率的相关性.
主要成果:
- 连续的ZIF-8外最初是在合体大小的粒子上形成的.
- 在生长过程中,几何挫折驱动了转化为黄结构的过程.
- 核心粒子的局部表面曲率显著影响得到的外形态.
结论:
- 一种曲率驱动的机制控制了黄ZIF-8结构的形成.
- 建立了一个设计原则,将核心表面几何与外形态联系起来.
- 这项工作为复杂的核心外纳米材料的自我组装提供了洞察力.
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