Alkali Halide‐Doped Ga₂S₃–GeS₂ Glasses

Abstract

Glass‐forming region, macroscopic properties, and electrical conductivity changes are systematically studied in the MY–Ga2S3–GeS2 systems, where M = Na, K, Rb and Y = Cl, Br, I, as a function of alkali concentration, MY chemical composition, and Ga2S3/GeS2 ratio using two composition lines: series A – (MY)x(Ga2S3)0.2–0.2x(GeS2)0.8–0.8x and series B – (MY)x(Ga2S3)0.2 + 0.2x(GeS2)0.8−1.2x. Glasses of series B are characterized by higher maximum MY concentration, increasing with the cation radius up to 66.7 mol% in case of RbCl. The halide nature is found to be less significant for the vitrification ability. The density of samples varies monotonically between the two end‐members of each series. Glass transition temperature decreases with increasing alkali concentration, ranging from 426 °C (x = 0) to 237 °C for (RbCl)67(Ga2S3)33 sample. The conductivity of MY–Ga2S3–GeS2 glasses decreases with increasing cation radius. The Ga2S3/GeS2 ratio and the halide nature affect the conductivity weakly.

Potentiometric Chemical Sensors Based on Metal Halide Doped Chalcogenide Glasses for Sodium Detection

“…The glass-forming region, macroscopic, and electrical properties for single cation sodium halide doped Ga 2 S 3 -GeS 2 glasses are already published in [13]. Our results for (NaHal) 15 (Ga 2 S 3 ) 23 (GeS 2 ) 62 compositions (Hal = Cl, I) are presented in the Table S1 (Supplementary Materials) and consistent with previous data.…”

“…The absence of Bragg peaks and the presence of broad diffraction bands confirm the amorphous nature of the (AgI) x (NaI) 30−x (Ga 2 S 3 ) 26 (GeS 2 ) 44 glasses where x = 7.5, 15 and 22.5 mol.% AgI (Figure 1a). The amorphous nature of sodium halide doped Ga 2 S 3 -GeS 2 glasses was already verified in our previous work [13].…”

“…The absence of Bragg peaks and the presence of broad diffraction bands confirm the amorphous nature of the (AgI)x(NaI)30−x(Ga2S3)26(GeS2)44 glasses where x = 7.5, 15 and 22.5 mol.% AgI (Figure 1a). The amorphous nature of sodium halide doped Ga2S3-GeS2 glasses was already verified in our previous work [13]. The soaking of the (AgI) x (NaI) 30−x (Ga 2 S 3 ) 26 (GeS 2 ) 44 glasses in the water over two weeks shows the degradation of the samples with x = 0, 7.5, 15, mol.% AgI.…”

“…Indeed, log σ25 = −5.00 (2) (S cm −1 ) and Eσ= 0.38 (1) eV were mentioned for (NaI)30(Ga2S3)26(GeS2)44 glass in Ref. [13] and σ25 = 1.2 × 10 −6 S cm −1 , Eσ= 0.3790 (16) eV are given for (AgI)30(Ga2S3)30(GeS2)40 vitreous solid in Ref. [28].…”

“…The content of sodium halide and the Ga 2 S 3 /GeS 2 ratio in the membrane composition could affect the performance of the chemical sensors. Recently, we have investigated the glass-forming regions, macroscopic properties, and Raman spectra in the NaY-Ga 2 S 3 -GeS 2 (Y = Cl, Br, I) systems [11][12][13][14]. The moisture resistant sodium halide doped Ga 2 S 3 -GeS 2 glasses could be obtained up to 15 mol.% NaY.…”