新型氧离子导体稳定氧化铋的中子衍射

Neutron Diffraction Study of New Stabilized δ-Bi_2O_3 Oxide Ion Conductors

摘要: 新型氧离子导体稳定氧化铋 (Dy2 O3) 0. 15-x(WO3) x(Bi2 O3) 0 85样品具有很高的电导率, 当x=0. 7时, 样品在 650℃经过 12 0 0h老化仍不发生相变。用中子衍射技术研究其结构, 发现氧离子在 32f晶位占位数随着x的变化有一极大值, 这时晶体结构趋向于氧离子由 8c晶位向 32f晶位移动。由于这时的 2 4e 32f键长最短, 结构极其稳定。

Abstract: Neutron diffraction is performed on samples of the new stabilized bismuth oxide(Dy 2O 3) 0.15- x (WO 3) x (Bi 2O 3) 0 85, which possess very high oxygen ionic conductivities. One of samples( x =0.7) is annealed at 650 ℃ for 1 200 h without structural change. Results show that for DWBO samples the occupation number of 32f sites increases to a maximum and the length of 24e 32f ionic bond decreases to a minimum with the change of x. It seems to be the reason of structural stability for DWBO( x =0.7) sample.