Energy-dispersive X-ray spectroscopy (EDX or EDS)
Present in a scanning electron microscope (SEM) the EDS detector can determine in a fast and easy way the qualitative or semi-quantitative elemental composition of very small sections. Obviously, this technique is significantly more useful for inorganic solids than organic ones since the later are always mainly composed of the same few elements (carbon, hydrogen (not detected by EDS) and oxygen).
In a SEM, while electrons are used to generate images, the EDS detector analyses the x-rays emitted from the sample to identify the elements present on the surface.
Type of samples: Inorganic solids (limited usefulness for organic solids)
Type of information: Elemental
Precision: Qualitative or semi-quantitative
Detection limit: as low as 0.1 atomic %
Depth of analysis: up to 5 microns
Smallest measurable area: 10 microns in diameters
Identification of inorganic materials (alloys, ceramics)
Good complement to scanning electron microscopy images
Fast, easy and inexpensive analysis
Can be used to analyse very small sections (few microns)
Elemental results only
Analysis in a vacuum (size and degassing issues for some samples)
Calibration and good sample preparation is needed for semi-quantitative analyses.
-Quick identification of alloys, ceramics, corrosion products, etc…
-Good option to narrow possible compounds when performing x-ray diffraction
Manufacturer : Hitachi
Model: S-4700 (cold FEG )