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Morphology of Melt-Quenched Lead Telluride Single Crystals.

ABSTRACT: Metastable single crystals of nonstoichiometric Pb_1-xTe are obtained by rapid cooling from the melt. The composition and crystallographic morphology are studied using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. Most single crystals have cubic, pyramidal, or hemispherical shapes with sizes ranging from 50 to 400 ?m. All crystals adopt the same face-centered cubic rock salt structure, and the crystal growth direction is ?100?. The bulk part of the rapidly cooled material solidifies in the form of a Te-rich polycrystalline material in which grains are separated by the PbTe-Te eutectic phase. The stabilization of nonstoichiometric Pb_1-xTe provides further scope for the optimization of lead telluride-based thermoelectric materials.

SUBMITTER: Lian H

PROVIDER: S-EPMC7883344 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Morphology of Melt-Quenched Lead Telluride Single Crystals.

Lian Hong H Ocelík Václav V Baas Jacob J Blake Graeme R GR

ACS applied materials & interfaces 20210129 5

Metastable single crystals of nonstoichiometric Pb<sub>1-<i>x</i></sub>Te are obtained by rapid cooling from the melt. The composition and crystallographic morphology are studied using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. Most single crystals have cubic, pyramidal, or hemispherical shapes with sizes ranging from 50 to 400 μm. All crystals adopt the same face-centered cubic rock salt structure, and the crystal ...[more]

PMID: 33512134

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