Electron energy loss spectroscopy (EELS) is a technique used in materials science and analytical chemistry to study the energy losses of electrons passing through a specimen. It is often performed using a transmission electron microscope (TEM) or a scanning transmission electron microscope (STEM).
In EELS, a beam of electrons is directed towards a thin section of a material, causing the electrons to interact with the atoms within the sample. As the electrons pass through the specimen, they lose energy due to scattering interactions with the atomic nuclei and the electrons in the material.
The amount of energy lost by the electrons is measured and analyzed to obtain information about the specimen's composition, bonding, electronic structure, and other properties. EELS can provide valuable insights into the elemental composition, chemical state, and local environment of atoms within a sample.
The technique allows researchers to investigate the energy loss due to excitation of different energy levels and electronic transitions, providing data on the density of states, electronic band structure, and optical properties of the material. EELS is especially useful for studying materials at the nanometer scale, such as nanoparticles, thin films, and interfaces.
EELS has applications in various fields, including materials science, nanotechnology, catalysis, energy storage, and biological research. It is a powerful tool for understanding the fundamental properties of materials and advancing our knowledge of their behavior and functionality.
