高温精密結晶構造解析によるイオン伝導性材料における可動イオン拡散経路の研究

抄録

The present paper is a brief review of our recent works on the crystal structures, structural disorders and ion-diffusion paths of various ionic and mixed conductors. Diffusion paths along the <100> directions are observed in the fluorite-type ionic conductors such as δ-Bi_1.4Yb_0.6O₃, Ce_0.93Y_0.07O_1.96, Y_0.785Ta_0.215O_1.715 and α-CuI. In the prerovskite-type and double-prerovskite-type conductors, the mobile oxide ions move along the <100> directions near the stable positions and along <110> around the midway of diffusion pathway. The cubic prerovskite-type and double-prerovskite-type conductors exhibit three- and two-dimensional networks of diffusion pathways, respectively. K₂NiF₄-type conductor has a two-dimensional network of diffusion pathway through interstitial oxide ions. The oxide ions in apatite-type conductors diffuse along the hexagonal c-axis. The diffusion paths of two lithium-ion conductors are also presented.