Institution: | a Department of Applied Chemistry, Faculty of Engineering, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa, Yokohama 221-8686, Japan b National Institute of Advanced Industrial Science and Technology-Kansai, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan |
Abstract: | The electrical conductivity of the LaY1?xInxO3 (x=0.0–0.7) system has been studied from the viewpoint of crystal chemistry. The high temperature form of LaYO3 (x=0.0) was ascertained to be the Sm2O3-type (B-type rare earth) structure, not perovskite-type one. The X-ray diffraction (XRD) experiments revealed that the samples with x=0.05 and 0.10 were the mixed phase of Sm2O3-type and perovskite-type structure, and changed to perovskite phase in the range of x 0.20. From oxygen partial pressure dependence of the electrical conductivity, it was found that both the Sm2O3-type and the perovskite-type single phases showed hole conduction, but the mixed phase did oxide-ion one. The electrical conductivity of the LaY1?xInxO3 (x=0.0–0.7) system increased with increasing x, and showed the maximum value in the range of x=0.05–0.10, and then decreased with increasing x. The occurrence of oxide-ion conduction was discussed from the viewpoint of lattice distortion in the mixed phase. |