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Chemical Pressure Effect on the Stabilization of Rock-Salt ZnO-Li_n-2MeO_n-1 Solid Solutions Synthesized at High Pressure.

ABSTRACT: Metastable ZnO-Li_n-2MeO_n-1 (Me = Sc³⁺, Ti⁴⁺, Ta⁵⁺) solid solutions with a rock-salt structure were synthesized through the solid-state reaction of ZnO with Li_n-2Meⁿ⁺O_n-1 (n = 3, 4, 5) complex oxides at 7.7 GPa and 1300-1500 K. In all investigated systems, single-phase rock-salt solid solutions can be quenched down to ambient conditions in a wide (up to 80 mol% ZnO) concentration range. The phase composition, thermal stability, and thermal expansion of the recovered rock-salt solid solutions were studied by synchrotron powder X-ray diffraction. At ambient pressure, these solid solutions exhibit high thermal stability (up to 1000 K), with the decomposition temperature and decomposition products depending on the nature of the multiple charge cations.

SUBMITTER: Sokolov PS

PROVIDER: S-EPMC10419647 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Chemical Pressure Effect on the Stabilization of Rock-Salt ZnO-Lin-2MeOn-1 Solid Solutions Synthesized at High Pressure.

Sokolov Petr S PS Baranov Andrey N AN Solozhenko Vladimir L VL

Materials (Basel, Switzerland) 20230729 15

Metastable ZnO-Lin-2MeOn-1 (Me = Sc3+, Ti4+, Ta5+) solid solutions with a rock-salt structure were synthesized through the solid-state reaction of ZnO with Lin-2Men+On-1 (n = 3, 4, 5) complex oxides at 7.7 GPa and 1300-1500 K. In all investigated systems, single-phase rock-salt solid solutions can be quenched down to ambient conditions in a wide (up to 80 mol% ZnO) concentration range. The phase composition, ...[more]

PMID: 37570040

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