Quantitative measurement of hydrogen isotopes in titanium using laser-induced breakdown spectroscopy

Laser-induced breakdown spectroscopy (LIBS) has been considered a promising technology for nuclear safeguard inspection, especially for isotope content ratio determination, since it can be easily designed for portable, fast, and in situ measurement. However, it was a challenge to determine hydrogen isotopes in metal samples due to the unfavorable spectral interference, the poor calibration of the hydrogen content, and the small difference between the atomic emission intensity of hydrogen isotopes at around 656.28 nm. This paper presents the determination of hydrogen isotope contents ratio using LIBS under partially baseline-resolved conditions. The results show that by introducing a proper buffer atmosphere for the LIBS measurement, the resolution of the hydrogen and deuterium emissions could be improved, but still not enabled, by a baseline resolution with a moderate resolution spectrometer. However, with the method of integral intensity correction, the accurate quantitative measurement of hydrogen and deuterium contents in a metal matrix could be achieved. This work provided the possibilities for the further development of LIBS in hydrogen isotopes in in situ measurement for nuclear safeguards.