Morphotropy, isomorphism, and polymorphism of Ln{sub 2}M{sub 2}O{sub 7}-based (Ln = La-Lu, Y, Sc; M = Ti, Zr, Hf, Sn) oxides
- Russian Academy of Sciences, Semenov Institute of Chemical Physics (Russian Federation)
Structural studies of compounds of variable composition and measurements of their conductivity have made it possible to identify new oxygen-ion-conducting rare-earth pyrochlores, Ln{sub 2}Ti{sub 2}O{sub 7} (Ln = Dy-Lu) and Ln{sub 2}Hf{sub 2}O{sub 7} (Ln = Eu, Gd), with intrinsic high-temperature oxygen ion conductivity (up to 1.4 Multiplication-Sign 10{sup -2} S/cm at 800 Degree-Sign C). Twenty six systems have been studied, and more than 50 phases based on the Ln{sub 2}M{sub 2}O{sub 7} (Ln= La-Lu; M = Ti, Zr, Hf) oxides have been synthesized and shown to be potential oxygen ion conductors. The morphotropy and polymorphism of the Ln{sub 2}M{sub 2}O{sub 7} (Ln = La-Lu; M = Ti, Zr, Hf) rare-earth pyrochlores have been analyzed in detail for the first time. Thermodynamic and kinetic (growth-related) phase transitions have been classified with application to the pyrochlore family.
- OSTI ID:
- 22121695
- Journal Information:
- Crystallography Reports, Vol. 58, Issue 4; Other Information: Copyright (c) 2013 Pleiades Publishing, Ltd.; http://www.springer-ny.com; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7745
- Country of Publication:
- United States
- Language:
- English
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