Energy-Dispersive Total-Reflection Resonant Inelastic X-ray Scattering as a Tool for Elemental Speciation in Contaminated Water

Abstract

This work presents a state-of the-art analytical methodology, by which chemical state information on metallic elements is obtained for liquid samples in a fast and simple manner. This method overcomes limitations of conventional X-ray techniques, such as X-ray absorption spectroscopy, by applying resonant inelastic X-ray scattering under total reflection geometry (TRIXS). TRIXS is particularly applicable for the analysis of small quantity of liquid samples deposited on polished reflectors. This feature is relevant for the chemical speciation of metallic trace elements contained in water samples, since the degree of their toxicity depends crucially on the concentration of specific chemical species included. The analytical merits of the proposed methodology were studied at Elettra Sincrotrone Trieste and at the Brazilian Synchrotron Light Laboratory. Contaminated water samples with low concentration of different chromium and manganese compounds were measured. Results prove the analytical potential of the TRIXS technique in characterizing different chemical species of metallic elements in water samples.

The Potential of EuPRAXIA@SPARC_LAB for Radiation Based Techniques

“…The analysis of the collected signal shows that hidden on the peak tails there is valuable information about the chemical environment of the atom under study [76]. During the last decade, several works have been published showing the first applications of a novel RIXS tool (named EDIXS) for the discrimination, determination and characterization of chemical environments in a variety of samples and irradiation geometries and even combined with other spectroscopic techniques [76][77][78][79][80][81][82][83][84][85][86]. Due to its versatility, EDIXS was applied in the typical 45 • -45 • setup for inspection of the material bulk, in total reflection for the study of the most external atomic layers of a sample, in grazing incidence used for depth resolved chemical speciation analysis and even in confocal setup to obtain chemical state information in a 3D regime, reaching nanometric spatial resolution.…”

Depth profiling characterization of the titanium chemical state on electrode surfaces for technological applications

“…24 During the last decade, and thanks to the versatility of X-ray emission techniques, EDIXS allowed the successful characterization of a wide variety of samples, from energy storage materials 25 to contaminated waters. 26 The versatility of this technique can be extended to irradiation geometries and experimental setups. Several results were reported in the last few years regarding the application of EDIXS in different geometries with the aim of highlighting specic sample information: 45-45 for bulk inspections, 25,[27][28][29][30] total reection for surface analysis, 26,31 grazing incidence for surface studies [32][33][34] and even confocal setups for 3D explorations.…”

“…26 The versatility of this technique can be extended to irradiation geometries and experimental setups. Several results were reported in the last few years regarding the application of EDIXS in different geometries with the aim of highlighting specic sample information: 45-45 for bulk inspections, 25,[27][28][29][30] total reection for surface analysis, 26,31 grazing incidence for surface studies [32][33][34] and even confocal setups for 3D explorations. 35 It is interesting to note that EDIXS has already been successfully employed for the discrimination of multilayered metallic samples.…”

Identifying different states of lithiation of Li4Ti5O12 spinel by energy-dispersive inelastic X-ray scattering (EDIXS) spectroscopy

“…As a result, this novel methodology shows a fast acquisition, energy-scanning free experiments, low self-absorption effects and an objective interpretation of the results. As it has been widely probed, by applying EDIXS the local chemical environment of an element of interest can be studied in a variety of irradiation geometries and experimental setups commonly used by conventional techniques, such as total reflection [18] , grazing incidence [19] and confocal setups [20] .…”