Energy Dispersive X-ray Spectroscopy (EDS/EDX)
Energy Dispersive X-ray Spectroscopy (EDS or EDX) is an analytical technique used to identify and characterize the elemental composition of sample material.
Using a scanning electron microscope (SEM) equipped with an x-ray detector, atoms within a sample are excited by an electron beam. This beam interacts with the atom, displacing an electron out of its shell leaving behind a void. Another electron from a higher energy level fills this void in the lower orbital. The energy released during this event is relative to the number of shells the replacement electron has displaced from its original location, and to what shell the electron moves. This energy is emitted as x-rays, which are converted into voltage by the detector. The resulting data consists of counts corresponding to the number of x-rays at each energy level. The energy level of the emitted x-rays correlates to individual elements, while the proportional counts relates to the quantity of the element.
As shown in the diagram, the movement from the L shell to the K shell would produce a Kα emission. If the same K position is filled from the M orbital, a Kβ emission would be produced. Alpha (α) emissions have the highest energy, but beta (β) emissions can give further insight into the element analyzed. Some elements may have emission energy overlaps, however, secondary α or β emissions can be used to distinguish one element from another. The cumulative spectrum of the emission energies for an element is unique to that element so it can be used to identify unknown particles in a sample or determine sample composition.
EDS technology from Particle Technology Labs is useful for analyzing the elemental composition of sample material for elements of atomic mass 12 (Carbon) and up, and can also be used to quantify the elemental composition of a sample. Results can be used for foreign material identification, process troubleshooting, deformulation, among other uses.
Note, in order to be analyzed by EDS, sample material must be able to be dried down prior to analysis. Material types we test include metals, metal oxides, unknowns, pharmaceuticals, proteins, ceramics, and more.
Contact PTL to discuss if your sample and project is appropriate for Energy Dispersive X-ray Spectroscopy analysis, and how this analytical technique can provide valuable information to your project.