KnE Materials Science
ISSN: 2519-1438
The latest conference proceedings on physical materials, energy materials, electrical materials.
Electrical Properties of Tungstates Ln2(WO4)3 (Ln – Gd, Ho)
Published date: Oct 12 2016
Journal Title: KnE Materials Science
Issue title: IV Sino-Russian ASRTU Symposium on Advanced Materials and Processing Technology (ASRTU)
Pages: 103-108
Authors:
Abstract:
Electrical properties of Gd2(WO4)3 and Ho2(WO4)3 were studied and the type of charge carriers was determined. The studied compounds have a salt-like isle structure with isolated tetrahedrons. It crystallises in the Еu2(WO4)3 structural type, so-called ‘defective scheelite’, in which 1/3 of Ln sites are vacant, Ln2/3[VLn]1/3WO4. Predominant ionic conductivity in Ln2(WO4)3 (Ln = Gd, Ho) was established both by the EMF method and from independence of conductivity versus oxygen partial pressure. A minor contribution (4-11%) of the anion [WO4]2- transport was detected by the Tubandt method, which along with the results of the EMF technique proves the predominant oxygen conductivity.
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