两维材料的电子图解以深度亚流的分辨率
Nature
|July 20, 2018
概括
研究人员通过使用二维材料在电子显微镜中实现了亚流分辨率. 这种技术显著增强了单原子缺陷的成像,超过了传统方法.
科学领域:
- 材料科学
- 物理
- 电子显微镜
背景情况:
- 偏差校正电子显微镜使纳米结构的原子分辨率成像成为可能.
- 传统的二维材料方法仅限于~1 Å的分辨率,因为有对光束损坏的担忧.
- 最先进的电子显微镜在300keV的电压下工作,
研究的目的:
- 提高电子显微镜中的空间分辨率,使二维材料超出传统的数值孔径限制.
- 改善像MoS2这样的材料中单原子缺陷的成像对比度.
- 在高分辨率成像中克服光束能量和电子剂量所造成的限制.
主要方法:
- 使用带有像素阵列探测器的电子显微镜, 能够捕获全部传输的电子分布.
- 应用全场光谱来从完整的相位空间重建相位信息.
- 在80千电子伏的光束能量下运行, 以最小化移位损伤.
主要成果:
- 实现空间分辨率明显超过数值孔径限制,达到接近5α的信息限制.
- 显示了0.39 Å的阿贝衍射限制分辨率,比传统方法 (~0.98 Å) 显著改进.
- 在MoS2中显著提高了单原子缺陷的图像对比度.
结论:
- 与先进的探测器相结合,可为敏感材料提供超高分辨率电子显微镜.
- 这种方法克服了在较低,减轻损害的光束能量下成像二维材料的传统分辨率障碍.
- 能够对原子尺度上的缺陷进行详细的描述,这对于理解材料特性至关重要.
更多相关视频
相关概念视频
Electron Carriers
91.9K
Electron carriers can be thought of as electron shuttles. These compounds can easily accept electrons (i.e., be reduced) or lose them (i.e., be oxidized). They play an essential role in energy production because cellular respiration is contingent on the flow of electrons.
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...
91.9K
Electron Affinity
43.4K
The electron affinity (EA) is the energy change for adding an electron to a gaseous atom to form an anion (negative ion).
43.4K
Electron Behavior
109.1K
Overview
Electrons are negatively charged subatomic particles that are attracted to an orbit around the positively-charged nucleus of an atom. They reside in locations that are associated with energy levels called shells and are further organized into sub-shells and orbitals within each shell.
Electrons Orbit the Nucleus
Electrons are found in specific locations outside of the nucleus. The shell in which an electron resides indicates the general energy level of the electron: those closer to the...
Electrons are negatively charged subatomic particles that are attracted to an orbit around the positively-charged nucleus of an atom. They reside in locations that are associated with energy levels called shells and are further organized into sub-shells and orbitals within each shell.
Electrons Orbit the Nucleus
Electrons are found in specific locations outside of the nucleus. The shell in which an electron resides indicates the general energy level of the electron: those closer to the...
109.1K
Members Made of Elastoplastic Material
405
The behavior of elastoplastic materials under bending stresses, particularly in structural members with rectangular cross-sections, is crucial for predicting material responses and understanding failure modes. Initially, when a bending moment is applied, the stress distribution across the section follows Hooke's Law and is linear and elastic. This distribution means the stress increases from the neutral axis to the maximum at the outer fibers, up to the elastic limit.
As the bending moment...
As the bending moment...
405
Genetic Material
3.8K
Within the human body, a complex and detailed system of trillions of cells works in unison to sustain life. Each cell houses a nucleus, which contains 46 chromosomes divided into 23 pairs. Chromosomes are highly coiled structures made of the genetic material DNA. These chromosomes are essential carriers of genetic information, with half inherited from the mother through her egg and the other half from the father's sperm, combining to create the unique genetic makeup of an individual.
3.8K
Electron Transport Chains
112.6K
The final stage of cellular respiration is oxidative phosphorylation that consists of two steps: the electron transport chain and chemiosmosis. The electron transport chain is a set of proteins found in the inner mitochondrial membrane in eukaryotic cells. Its primary function is to establish a proton gradient that can be used during chemiosmosis to produce ATP and generate electron carriers, such as NAD+ and FAD, that are used in glycolysis and the citric acid cycle.
The ETC is comprised of...
The ETC is comprised of...
112.6K


