Development and validation of standardless and standards-based X-ray microanalysis

Abstract

We describe one approach to standardless quantification for energy-dispersive (ED) X-ray spectrometry that can achieved unnormalised results with an accuracy better than 5 %. This approach relies on a “factory” standards database, a model of the detector efficiency, calculated peak profiles, and a multi-step process to correct spectral artefacts and extract X-ray intensities from ED spectra. These processes and components, as well as the underlying equations involved in the quantification are detailed to illustrate the similarities between this approach and the classical standard-based k-ratio quantification. The accuracy was assessed by measuring and quantifying standard samples at different accelerating voltages (15 and 20 kV) and input count rates (50 and 200 kcps). In all cases, the measured, unnormalised concentrations yielded a centred distribution with a relative error less than 5 %. Excluding the analysis of light elements (B, C, O, N, F) improved the relative error to around 2 %

Lanthanide (Eu, Tb, La)-Doped ZnO Nanoparticles Synthesized Using Whey as an Eco-Friendly Chelating Agent

“…EDS data acquisition was performed at an accelerating voltage of 200 kV, fixed channel width of 10 eV (2048 channels and 20 keV energy range), and by simultaneously applying pulse pile up and absorption corrections. Quantitative EDS microanalysis was realized based on the Cliff-Lorimer method using theoretical k-factors incorporated in Aztec v4.3 [18,19]. Copper was used as the calibration element.…”

Improved Protocol for the Quantification of Actinides (Th, U, Np, Pu, Am, and Cm) Using Electron Probe Microanalysis

“…If reference materials are not available, other methods can be used to quantify the concentrations of an element. First, standardless or virtual reference procedures are highly promising as reported in Limandri et al (2012), Trincavelli et al (2014), Moy et al (2014, 2015), and Pinard et al (2020), which are accompanied by an error of 9% for heavy elements (Moy et al, 2014, 2015). Second, specifically for the quantification of Am, a missing reference for Am can be replaced by measuring the Am in-growth in the PuO 2 material.…”

Measurement and Calculation of X-Ray Production Efficiencies for Copper, Zirconium, and Tungsten

“…Oxford Instruments applied a synchrotron calibrated EDS to improve the quantitative analysis (Statham, 2009). By means of this EDS, the “factory” standards data base was created (Pinard et al, 2020).…”

“…The simplest way consists in the determination of empirical sensitivity factors by the user to correct differences between the analysis result and the composition of a reference material. Pinard et al (2020) describe an alternative concept of so-called “factory” standards. It is based on measured X-ray spectra of a large number of reference materials.…”