Trace‐element XAFS sensitivity: a stress test for a new XRF multi‐detector

• Published in: Journal of synchrotron radiation 2021-11, Vol.28 (6), p.1811-1819
• Main Authors: Carlomagno, Ilaria, Antonelli, Matias, Aquilanti, Giuliana, Bellutti, Pierluigi, Bertuccio, Giuseppe, Borghi, Giacomo, Cautero, Giuseppe, Cirrincione, Daniela, de Giudici, Giovanni, Ficorella, Francesco, Gandola, Massimo, Giuressi, Dario, Medas, Daniela, Mele, Filippo, Menk, Ralf H., Olivi, Luca, Orzan, Giulio, Picciotto, Antonino, Podda, Francesca, Rachevski, Alexandre, Rashevskaya, Irina, Stebel, Luigi, Vacchi, Andrea, Zampa, Gianluigi, Zampa, Nicola, Zorzi, Nicola, Meneghini, Carlo
• Format: Article
• Language: English
• Subjects: Data analysis; Ecosystem; Evaluation; Exercise Test; Fluorescence; fluorescence detector; geology; Human influences; Humans; Manganese; Metals; Oxidation; Research Papers; Sensors; Signal quality; Speciation; Spectrum analysis; Trace elements; Trace Elements - analysis; Valence; Volcanic activity; X-Ray Absorption Spectroscopy; X‐ray fluorescence
• ISSN: 1600-5775; 0909-0495; 1600-5775
• DOI: 10.1107/S1600577521008857

X‐ray absorption fine‐structure (XAFS) spectroscopy can assess the chemical speciation of the elements providing their coordination and oxidation state, information generally hidden to other techniques. In the case of trace elements, achieving a good quality XAFS signal poses several challenges, as it requires high photon flux, counting statistics and detector linearity. Here, a new multi‐element X‐ray fluorescence detector is presented, specifically designed to probe the chemical speciation of trace 3d elements down to the p.p.m. range. The potentialities of the detector are presented through a case study: the speciation of ultra‐diluted elements (Fe, Mn and Cr) in geological rocks from a calcareous formation related to the dispersal processes from Ontong (Java) volcanism (mid‐Cretaceous). Trace‐elements speciation is crucial in evaluating the impact of geogenic and anthropogenic harmful metals on the environment, and to evaluate the risks to human health and ecosystems. These results show that the new detector is suitable for collecting spectra of 3d elements in trace amounts in a calcareous matrix. The data quality is high enough that quantitative data analysis could be performed to determine their chemical speciation. A new multielement X‐ray fluorescence detector is presented, specifically designed to probe the chemical speciation of trace 3d elements down to the p.p.m. range.