Introduction to the applications of transmission electron microscopy (TEM)
Morphological observation: By using thick contrast (also known as absorption contrast) images, the morphology of the sample can be observed, which can clearly present the surface morphology and internal structure contour of the sample, providing intuitive basis for the study of the appearance characteristics of the material.
Phase analysis: By using techniques such as electron diffraction, micro area electron diffraction, and convergent beam electron diffraction, the phase of the sample is analyzed. By determining the phase, crystal system, and even space group of materials, we can delve into the crystal structure and composition of materials, providing a theoretical basis for predicting their properties and developing applications.
Crystal structure determination: By using high-resolution electron microscopy, the structural projection of atoms or atomic clusters in a specific direction in the crystal can be directly observed. This feature enables researchers to accurately determine the crystal structure, providing key information for the study of material microstructure and the design and synthesis of new materials.
Structural defect observation: Using diffraction contrast imaging and high-resolution electron microscopy techniques, observe structural defects present in the crystal, such as dislocations, dislocations, grain boundaries, etc. By identifying the types of defects and estimating defect density, researchers can gain a deeper understanding of the relationship between the mechanical and physical properties of materials and their microstructure, providing guidance for material performance optimization and defect control.
Micro area chemical composition analysis: Using an energy dispersive X-ray spectrometer or electron energy loss spectrometer attached to TEM to analyze the micro area chemical composition of the sample. This analytical method can reveal the elemental distribution and chemical composition of materials at the microscale, providing strong support for research on corrosion, oxidation, doping, and other aspects of materials.
In situ observation of dynamic processes: With the help of heating and strain devices attached to TEM, researchers can observe the microstructural changes of samples during heating, deformation, fracture, and other processes in situ. This real-time observation provides a new perspective for understanding the dynamic behavior and failure mechanism of materials, which is helpful for developing high-performance and high reliability materials.
In the field of nanomaterials research, transmission electron microscopy can accurately measure the size, morphology, and crystal structure of nanoparticles. Through high-resolution imaging technology, researchers can clearly observe the lattice constant and surface atomic arrangement of nanomaterials.
