Instant elemental and valence mapping with GIF Continuum using internal standards
Gatan instrument used
GIF Continuum® system
Background
Analytical electron microscopy has proven valuable in numerous research areas by revealing chemical information inside a sample. The two most popular analytical techniques in transmission electron microscopy (TEM) are energy dispersive x-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS). In addition to the high-collection efficiency of the forward scattered electrons relative to emitted x-rays during elemental mapping, another exclusive advantage of EELS over EDS is chemical state analysis. A detailed analysis of the energy loss near-edge fine structure (ELNES) can reveal information about specific elements that EDS spectra cannot, such as valence states. For example, in corrosion science, analyzing the valence states is critical for understanding which phase forms during redox reactions. Furthermore, the distribution of each phase provides clues to the kinetics of the corrosion behavior, thus leading to a discussion on the fundamental corrosion mechanism of metal materials.