Morphotropy, isomorphism, and polymorphism of Ln (2) M O-2(7)-based (Ln = La-Lu, Y, Sc; M = Ti, Zr, Hf, Sn) oxides

作者：Shlyakhtina A V^*

来源：Crystallography Reports, 2013, 58(4): 548-562.

DOI：10.1134/S1063774513020259

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 2Ti2O7 (Ln = Dy-Lu) and Ln 2Hf2O7 (Ln = Eu, Gd), with intrinsic high-temperature oxygen ion conductivity (up to 1.4 x 10(-2) S/cm at 800A degrees C). Twenty six systems have been studied, and more than 50 phases based on the Ln (2) M O-2(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 (2) M O-2(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.

• 出版日期2013-7