elektronenergiförlustspektroskopi

Elektronenergiförlustspektroskopie, often abbreviated as EELS, is an analytical technique used in transmission electron microscopy (TEM) to probe the elemental composition and electronic structure of a sample. It works by measuring the energy lost by electrons that have passed through a thin specimen. As these primary electrons interact with the sample, they can undergo inelastic scattering, losing a portion of their kinetic energy. This energy loss is specific to the material's composition and bonding.

The energy loss spectrum obtained from EELS provides information about the atoms present in the sample, their oxidation states, and the types of chemical bonds they form. Characteristic energy loss peaks correspond to the excitation of core-level electrons or plasmons. By analyzing these peaks, researchers can identify elements, determine their distribution within the sample, and gain insights into the local electronic environment. EELS is particularly powerful for analyzing light elements, which are difficult to detect with energy-dispersive X-ray spectroscopy (EDS). The technique requires a monochromatic electron beam and a high-resolution spectrometer, typically integrated into a TEM. Its applications span a wide range of fields, including materials science, nanoscience, and solid-state physics.