Origin of Colossal Dielectric Behavior In Double Perovskite Ba2CoNbO6. Issue 7 (15th April 2013)

• Record Type: Journal Article
• Authors: Wang, Guojing; Wang, Chunchang; Huang, Shouguo; Lei, Changmei; Sun, Xiaohong; Li, Teng; Liu, Lina; Jones, J.
• Is Part Of: Journal of the American Ceramic Society. Volume 96:Issue 7(2013)
• Page Start: 2203
• Page End: 2210
• Publication Date: 2013-04-15
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.12318
• Languages: English
• ISSNs: 0002-7820

Abstract

<abstract abstract-type="main" xml:lang="en" id="jace12318-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Ba₂CoNbO₆ ceramic samples were synthesized by solid‐state reaction technique. X‐ray photoemission spectroscopy reveals the coexistence of mixed‐valent structure of Co²⁺/Co³⁺ in the sample. Dielectric measurements reveal that the sample shows colossal dielectric behavior. This behavior is contributed by two thermally activated dielectric relaxations: the low‐temperature relaxation is a polaron relaxation resulting from the hopping motions of self‐trapped holes; the high‐temperature relaxation is a Maxwell–Wagner relaxation caused by the grain‐boundary response. Our results indicate a multirelaxation mechanism, i.e., the coupling of the polaronic relaxation and the Maxwell–Wagner relaxations might be a common origin of the colossal dielectric behavior found in different materials.</p> </abstract>