Wavelength dispersive x‐ray fluorescence spectrometry for the analysis of laser active lanthanides (Ln) in NaT_1−xLn_x(WO₄)₂ crystals

Abstract

Four crystals with nominal compositions, NaLa 0.95 Tm 0.05 (WO 4 ) 2 (1.32 wt% of Tm), NaGd 1−x Tm x (WO 4 ) 2 x = 0.05, 0.07 (1.24 and 1.32 wt% of Tm, respectively) and NaY 0.9 Yb 0.1 (WO 4 ) 2 (2.81 wt% of Yb), were analyzed by wavelength dispersive x-ray fluorescence spectrometry. A procedure for sample preparation was developed using lithium tetraborate as flux to obtain glass disks and to circumvent precipitation problems of lanthanides and tungsten experienced in their dissolution by wet routes. For this purpose three specific calibration standards with pure oxides were prepared for each analyzed element with near to constant W and Na concentrations, so that matrix effects could be properly addressed. The procedure allows measurement of the Tm and Yb concentrations above the determination limits of 0.017 wt% and 0.042 wt% for Tm in the first two crystals, respectively, and of 0.039 wt% of Yb in the last one. Further analyses show an excess with regard to the nominal formula of ≈5 mol% in the total concentration of trivalent ions incorporated to the crystal and some deficiency of Na (≈10 mol%) and W (≈2 mol%) ions. ConclusionsAn analytical procedure based on the melting of Na-based double tungstate crystals in Li 2 B 4 O 7 flux and the cooling down to form glass disks has been developed to evaluate the content of laser X-Ray Spectrom.

A roadmap for laser optimization of Yb:Ca3(NbGa)5O12-CNGG-type single crystal garnets

“…Na concentration was also evaluated by Wavelength Dispersive X-Ray Fluorescence (WDXRF) using a MagiX sequential spectrometer and methods described in a previous work. 28 For the latter purpose specific Na standards were developed for calibration as explained in the ESI, † see Fig. S5, and the interference between Ga and Na X-ray emissions was explicitly considered, see Fig.…”

Determination of rare earth elements by spectroscopic techniques: a review

“…Non-destructive determination of REE in laser crystals has been proposed by Valle et al 136 Four crystals with NaLa 0.95 Tm 0.05 (WO 4 ) 2 , NaGd 1-x Tm x (WO 4 ) 2 x ¼ 0.05, 0.07, and NaY 0.9 Yb 0.1 (WO 4 ) 2 compositions were analyzed by wavelength dispersive X-ray fluorescence spectrometry. The crystals were analyzed as glass disks after fusion using lithium tetraborate as flux.…”

Atomic spectrometry update–X-ray fluorescence spectrometry

“…There are only two papers to mention in this review concerning the fused bead preparation technique. Valle et al 165 published their method for the analysis of laser active lanthanides (Ln) in NaTm 1-x Ln x (WO 4 ) 2 crystals. A method was developed to circumvent precipitation problems, involving lanthanides and tungsten, experienced during wet chemical dissolution.…”