X-ray fluorescence (XRF) is a powerful and non-destructive analytical technique used to determine the concentrations of elements in a material.fluorescence analyzer The process works by striking a sample with an X-ray beam from an X-ray tube which causes the material to excite and then fluoresce, producing characteristic X-rays which are unique to each element in the material. The characteristic X-rays are detected by the detector and the elemental concentration is determined using fundamental parameters or user-generated calibration curves.
In a typical analysis a sample of rocks, ores and sediments is ground into a fine powder before being passed through a tube for X-ray excitation.fluorescence analyzer This primary X-ray beam illuminates the sample, which is then subjected to a secondary beam of X-rays produced by the interaction between the material and an electron. This energy is transferred to the sample atoms, causing them to become ionised, and as the ions are ejected they release their tightly held inner electrons to replace them with outer ones. The resulting characteristic X-rays are released in the form of fluorescent radiation with wavelengths corresponding to the energy difference between the electron orbitals that were occupied by these two different electron levels in each of the atoms in the sample.
This characteristic X-ray emission is then recorded by the detector, and as the energy positions of the characteristic X-rays are consistent for each element it is possible to identify the composition of the sample based on the peaks in the X-ray spectrum.fluorescence analyzer However, because the peaks can overlap and the energy positions are not necessarily precise, the results of an XRF analysis are best used for qualitative identification of the sample rather than quantitative determination of the elemental concentrations.
To improve the accuracy of the XRF results, the fluorescent radiation is separated into its components by sorting the energies (energy-dispersive analysis) or by separating the wavelengths of the characteristic radiation (wavelength-dispersive analysis).fluorescence analyzer The intensity of each component is proportional to the amount of that element present in the sample, enabling its concentration to be determined.
A combination of these techniques is the most widely used method for the determination of major and trace elements in geological samples.fluorescence analyzer XRF is known for its ability to provide concentrations even when the sample matrix is unknown, although this method is most accurate when the samples are free of contamination such as alloys or oxides.
SPECTRO offers a wide range of portable handheld XRF analyzers including the XEPOS, XSORT and SPECTROSCOUT for specialized elemental analysis in the field as well as an extensive selection of benchtop XRF spectrometers for laboratory use.fluorescence analyzer In addition, SPECTRO offers a number of online XRF solutions for rapid analysis of samples in remote locations. Contact us to discuss your requirements and find out how SPECTRO can help. Our experts can guide you to the most suitable solution. Alternatively, you can request a quote for your specific application.