Chemical ordering in Ge20Se80−χInχ glasses

doi:10.1016/0022-3093(94)00699-7

Journal of Non-Crystalline Solids

Volume 188, Issues 1–2, 2 July 1995, Pages 98-106

https://doi.org/10.1016/0022-3093(94)00699-7 Get rights and content

Abstract

Bulk glasses of GeSeIn have been prepared by quenching the melt and have been subjected to thermal crystallization and X-ray structure analysis of devitrified materials. These glasses show a transformation from a single-stage to a double-stage crystallization with respect to composition. The present investigations indicate that these materials are structurally inhomogeneous at a molecular level, in which In₂Se₃ microclusters are dispersed in the GeSe matrix. These results are discussed using the chemical threshold in glasses.

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Moreover, Ge-based chalcogenide with a structure similar to black phosphorus has attracted wide attention [26–28]. Furthermore, various binary and ternary of Ge-based chalcogenide were invested, such as GeSe [29], GeS [30], Ge-Se-Ag [31], In doped GeSe [32], Ge-Sn-Se and Ge-Se-Te [33]. It is worth mentioning that Ge0.9Sb0·1Te0·9Se0·05S0.05 showed a high ZT of 2.1 at 630 K [34], G. Ding et al. [35] have investigated the thermoelectric properties of GeS, GeSe, SnS and SnSe compounds using first-principles combined with the Boltzmann transport theory.
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Many works are performed on Ge–In–Se system. Rabinal et al. [7] studied the thermal crystallization of Ge20Se80-xlnx and they found that all compositions show single stage glass transition while the system shows single stage crystallization up to 12% of In content and double stage crystallization appears for more incorporation. In addition to that, El-Gendy et al. [8] reported that the thermal stability of Ge15Se85-xlnx system increases by increasing In content.
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Chemical ordering in Ge20Se80−χInχ glasses

Abstract

J. Non-Cryst. Solids

J. Non-Cryst. Solids

J. Non-Cryst. Solids

Solid State Commun.

J. Non-Cryst. Solids

J. Non-Cryst. Solids

Mater. Sci. Eng.

Scripta Metall.

J. Non-Cryst. Solids

Physica

J. Non-Cryst. Solids

Philos. Mag.

Philos. Mag.

Philos. Mag.

Phys. Rev.

Jpn. J. Appl. Phys.

Chemical ordering in Ge₂₀Se_80−χIn_χ glasses