Ultra-low thermal conductivity in scheelite and A-deficient scheelite ceramics

SCRIPTA MATERIALIA

卷:201

Article

Bsaibess, Eliane¹  Delorme, Fabian¹  Monot-Laffez, Isabelle¹  Giovannelli, Fabien¹ 

[1] Univ Tours, CNRS, UMR 7347, INSA CVL,GREMAN,IUT Blois, 15 Rue Chocolaterie, F-41029 Blois, France

关键词: Molybdenum-based scheelites;    Defect scheelite-type;    Low thermal conductivity;    Solid-state synthesis;   

DOI  :  10.1016/j.scriptamat.2021.113950

来源: Elsevier

【 摘 要 】

Synthesis of scheelite-type oxides based on lanthanum and barium molybdate (BaMoO4 and La2Mo3O12 ceramics) were successfully prepared via conventional solid-state reaction method. Dense ceramics were obtained by conventional sintering. Structural, microstructural and thermal properties of both sintered ceramics were assessed to identify the impact of cation deficiency on thermal conductivity. BaMoO4 ceramic has shown a decrease in thermal conductivity from 0.8 W m(-1) K-1 to 0.65 W m(-1) K-1 from 400 K to 650 K. The deficient scheelite La2Mo3O12 compound was found to further reduce thermal conductivity. An ultra-low thermal conductivity constant value of about 0.59-0.62 W m(-1) K-1 was calculated over the entire temperature range. This value is the lowest recorded value for oxides so far discovered and such materials may be promising ones for thermal insulating applications. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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