Deuterium analysis by inductively coupled plasma mass spectrometry using polyatomic species: An experimental study supported by plasma chemistry modeling

Gábor Galbács; Albert Kéri; Ildikó Kálomista; Éva Kovács-Széles; Igor B Gornushkin

doi:10.1016/j.aca.2020.01.011

Deuterium analysis by inductively coupled plasma mass spectrometry using polyatomic species: An experimental study supported by plasma chemistry modeling

Anal Chim Acta. 2020 Apr 1:1104:28-37. doi: 10.1016/j.aca.2020.01.011. Epub 2020 Jan 13.

Authors

Gábor Galbács¹, Albert Kéri², Ildikó Kálomista², Éva Kovács-Széles³, Igor B Gornushkin⁴

Affiliations

¹ Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm Square 7, 6720, Szeged, Hungary. Electronic address: galbx@chem.u-szeged.hu.
² Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm Square 7, 6720, Szeged, Hungary.
³ Nuclear Security Department, MTA Centre for Energy Research, Konkoly Thege Miklós Street 29-33, 1121, Budapest, Hungary.
⁴ BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Strasse 11, 12489, Berlin, Germany.

PMID: 32106954
DOI: 10.1016/j.aca.2020.01.011

Abstract

A new analytical method is proposed for the determination of deuterium (D) by ICP-MS. The method is based on the use of the signal from hydrogen-containing polyatomic ions formed in the inductively coupled plasma. Prior to analytical experiments, a theoretical study was performed to assess the concentration of polyatomic species present in an equilibrium Ar-O-D-H plasma, as a function of temperature and stoichiometric composition. It was established that the highest sensitivity and linearity measurement of D concentration in a wide range can be achieved by monitoring the ions of D₂ and ArD, at masses 4 and 42, respectively. Results of the calculations are in good agreement with the experiments. Signal stability, spectral interferences, as well as the effect of plasma parameters were also assessed. Under optimized conditions, the limit of detection (LOD) was found to be 3 ppm atom fraction for deuterium when measured as ArD (in calcium and potassium free water), or 78 ppm when measured as D₂. The achieved LOD values and the 4 to 5 orders of magnitude dynamic range easily allow the measurement of deuterium concentrations at around or above the natural level, up to nearly 100% (or 1 Mio ppm) in a standard quadrupole ICP-MS instrument. An even better performance is expected from the method in high resolution ICP-MS instruments equipped with low dead volume sample introduction systems.

Keywords: Deuterium; Deuterium-depleted water; Deuterium-enriched water; Hydrogen; Inductively coupled plasma-mass spectrometry; Polyatomic species.