Nielsen Michael H, Li Dongsheng, Zhang Hengzhong, Aloni Shaul, Han T Yong-Jin, Frandsen Cathrine, Seto Jong, Banfield Jillian F, Cölfen Helmut, De Yoreo James J
1 Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA 94720, USA.
2 Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
Microsc Microanal. 2014 Apr;20(2):425-36. doi: 10.1017/S1431927614000294. Epub 2014 Mar 14.
Recent ex situ observations of crystallization in both natural and synthetic systems indicate that the classical models of nucleation and growth are inaccurate. However, in situ observations that can provide direct evidence for alternative models have been lacking due to the limited temporal and spatial resolution of experimental techniques that can observe dynamic processes in a bulk solution. Here we report results from liquid cell transmission electron microscopy studies of nucleation and growth of Au, CaCO3, and iron oxide nanoparticles. We show how these in situ data can be used to obtain direct evidence for the mechanisms underlying nanoparticle crystallization as well as dynamic information that provide constraints on important energetic parameters not available through ex situ methods.
近期对天然和合成体系中结晶过程的非原位观察表明，经典的成核和生长模型并不准确。然而，由于能够在本体溶液中观察动态过程的实验技术在时间和空间分辨率上有限，缺乏能够为替代模型提供直接证据的原位观察。在此，我们报告了利用液体池透射电子显微镜对金、碳酸钙和氧化铁纳米颗粒的成核和生长进行研究的结果。我们展示了如何利用这些原位数据获得纳米颗粒结晶背后机制的直接证据，以及提供对非原位方法无法获得的重要能量参数进行约束所需的动态信息。
