电子断层扫描以2.4英的分辨率进行
M C Scott1, Chien-Chun Chen, Matthew Mecklenburg
1Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, California 90095, USA.
Nature
|March 23, 2012
概括
一种新的通用电子断层扫描方法可以在没有先前的结构假设的情况下对纳米材料进行原子规模的3D成像. 这项技术为金纳米粒子实现了2.4安格斯特罗姆分辨率,揭示了其详细的形态和格子结构.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米科学是一个纳米科学.
- 生物学 生物学 生物学
- 电子显微镜电子显微镜
背景情况:
- 传输电子显微镜 (TEM) 为材料科学,纳米科学和生物学提供了强大的成像.
- 偏差校正的电子镜头显著提高TEM分辨率,达到0.5 Ångströms以下.
- 电子断层扫描对于细样本的3D结构确定至关重要,目前的立方纳米分辨率.
研究的目的:
- 展示用于原子级分辨率3D成像的一般电子断层扫描方法.
- 为了克服离散断层扫描的局限性,这需要先前了解格子结构.
- 将该方法应用于金纳米粒子并描述其结构.
主要方法:
- 复合扫描传输电子显微镜 (STEM) 采用新的投影对齐和断层扫描重建方法.
- 开发了一种一般的电子断层扫描方法,没有关于样本结构的初步假设.
- 实现了原子级分辨率成像.
主要成果:
- 在2.4 ångström分辨率下确定了~10nm金纳米粒子的3D结构.
- 观察了特定区域的单个原子,并在三维中确定了几个粒.
- 揭示了3D表面形态和内部格子结构,与扭曲的二面体多重双胞胎粒子一致.
结论:
- 展示的通用电子断层扫描方法实现了纳米材料的原子尺度分辨率.
- 这种技术提供了纳米粒子结构的洞察力,没有先前的结构假设.
- 该方法在各种断层扫描领域具有潜在的应用,以提高分辨率和图像质量.
相关概念视频
01:07Electron Microscope Tomography and Single-particle Reconstruction
Transmission electron microscopy (TEM) can be used to determine the 3D structure of biological samples with the help of techniques such as electron microscope tomography and single-particle reconstruction. While single-particle reconstruction can examine macromolecules and macromolecular complexes in vitro conditions only, tomography permits the study of cell components or small cells in vivo.
Electron Tomography
Electron tomography can be performed either in TEM or STEM (scanning transmission...
Electron Tomography
Electron tomography can be performed either in TEM or STEM (scanning transmission...
01:25Overview of Electron Microscopy
The wavelengths of visible light ultimately limit the maximum theoretical resolution of images created by light microscopes. Most light microscopes can only magnify 1000X, and a few can magnify up to 1500X. Electrons, like electromagnetic radiation, can behave like waves, but with wavelengths of 0.005 nm, they produce significantly greater resolution up to 0.05 nm as compared to 500 nm for visible light. An electron microscope (EM) can create a sharp image that is magnified up to 2,000,000X.
01:15Transmission Electron Microscopy
In 1931, physicist Ernst Ruska—building on the idea that magnetic fields can direct an electron beam just as lenses can direct a beam of light in an optical microscope—developed the first prototype of the electron microscope. This development led to the development of the field of electron microscopy. In the transmission electron microscope (TEM), electrons are produced by a hot tungsten element and accelerated by a potential difference in an electron gun, which gives them up to 400 keV in...