Position dispersive X-ray fluorescence

A novel scanning-free wavelength dispersive X-ray fluorescence spectrometer has been developed by combining low power X-ray tubes with X-ray optics. The X-rays are focused to a single point on the sample and then dispersed onto a flat diffracting crystal where they are spread depending on their energy through Bragg's law of diffraction onto a silicon strip detector. Throughout this study, the proposed method is referred to as Position Dispersive X-ray Fluorescence (PDXRF). The X-ray emission spectra of vanadium and copper as well as, CuO, CuS2 and V2O5 were measured. In the spectrometer energy resolutions of 3.14 eV and 8.94 eV FWHM were measured for V and Cu when measuring over a range of 4.8–5.8 keV and 6.2–9.1 keV respectively. The Kβ line shapes were fitted with a series of Voigt profiles and the energies and intensities of the Kβ valence transition peak, Kβ2,5, were determined. There was also sufficient variation in the intensity ratio of Kβ2,5/Kβ1,3 that the oxygen and sulphur compounds of V and Cu could be successfully observed and measured. The result demonstrates that this experimental setup is capable of measuring the Kβ line shape at resolutions of a few eV, allowing for chemical state analysis to be performed on 3d transition metals and their compounds such as the measurement of redox reactions to aid in battery development. © 2022