Macroscopic phase separation of Se-rich (x< 1/3) ternary Ag_y(Ge_xSe_1 x)_1 yglasses

Abstract

Temperature modulated differential scanning calorimetry measurements on Agy(GexSe1−x) 1−y glasses provide evidence for bimodal glass transition temperatures in Se-rich glasses (x < 1/3). At x = 0.20 and 0.25, thermal measurements performed as a function of Ag content in the 0 ≤ y ≤ 0.25 range reveal that the additive (Ag) segregates into an Ag2Se-rich glass phase, possessing a characteristic glass transition temperature Tga = 230° C, while the remaining base glass displays a second glass transition temperature Tgb that systematically increases as its Se content is depleted. The present thermal results are in harmony with Raman scattering, neutron diffraction, dielectric spectroscopy and optical microscopy measurements and suggest that Se-rich glasses in the Ag–Ge–Se ternary system intrinsically phase separate on a macroscopic scale.

Signature of a silver phase percolation threshold in microscopically phase separated ternary Ge0.15Se0.85−xAgx (⩽x⩽0.20) glasses

“…5,6 As mentioned earlier, in the rerun of the samples, only one T g which corresponds to Ge 0.15 Se 0.85 backbone is seen. However, it has been found that the glass transition temperatures in the second runs are marginally higher than those of the first runs [ Fig.…”

“…[1][2][3] Glasses on the selenium-rich side of the Ge-Se-Ag system are fast ionic conductors with silver as the mobile cation. Although several studies have been undertaken on Ag-doped chalcogenide glasses, especially on Ge-Se-Ag systems, [4][5][6][7] the microscopic structure of these glasses is not fully understood.…”

“…Ternary Ge-Se-Ag glasses can be formed in two distinct composition regions, 5,6,8 namely, a Se-rich region labeled as I, and a Ge-rich region labeled as II (Fig. 1).…”

AgGeSe-based bulk glasses: A survey of their fundamental properties

“…However this is only a rough approximation as both phases contain Ag as has been reported in [9]. Phase separation in Ag-Ge-Se bulk glasses in the subsystem -Se-GeSe 2 has also been reported by [10,11]. These authors indirectly observed glass inhomogeneity employing different techniques.…”

Pore Structure and Interconnectivity of CdS Aerogels and Xerogels by Hyperpolarized Xenon NMR

“…These properties, combined with the porous architecture, make them uniquely suited for a range of potential applications, including photocatalysis and optical sensing. [12][13][14][15][16][17][18][19][20] Additionally, related chalcogels prepared from condensation of molecular anionic clusters and * To whom correspondence should be addressed. E-mail: shane.pawsey@ bruker-biospin.com (S.P.…”