Thermal stability and high temperature polymorphism of topochemically-prepared Dion-Jacobson triple-layered perovskites

JOURNAL OF ALLOYS AND COMPOUNDS

卷:647

Article

Wiley, John B.¹ 

[1] Univ New Orleans, Dept Chem, New Orleans, LA 70148 USA

关键词: Oxide materials;    Preferential site ordering;    Phase transitions;    Calorimetry;    X-ray diffraction;   

DOI  :  10.1016/j.jallcom.2015.06.045

来源: Elsevier

【 摘 要 】

The thermal stability of six Dion-Jacobson-related triple layered perovskites, ACa(2)Nb(3)O(10) (A = H, NH4, Li, Na, K, CuCl), was explored to 1000 degrees C. Each compound was produced topochemically by low-temperature (<500 degrees C) ion exchange from RbCa2Nb3O10. The thermal behavior of the series was examined by variable temperature X-ray powder diffraction experiments in tandem with thermogravimetric analysis and differential scanning calorimetry. Five of the species were found to be low temperature/metastable phases, decomposing below 900 degrees C, where the stability of the series decreased with decreasing interlayer cation size. The compounds, A = Li, Na, K, exhibited high temperature polymorphism, with a completely reversible transition evident for KCa2Nb3O10. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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