Structural phase transition and ion conductivity in 0.88ZrO 2−0.12Sc 2O 3

Abstract

It is found that oxygen ion conductor 0.88ZrO 2−0.12Sc 2O 3 shows a discontinuous change in ion conductivity and a structural phase transition at around 650°C. The temperature dependence of ion conductivity shows a clear hysteresis at transition temperature. The crystal structure changes reversibly from rhombohedral to cubic at the transition temperature. The compound 0.88ZrO 2− 0.12Sc 2O 3 exhibits a first-order phase transition to a fast oxygen-ion conductor. The high temperature phase with fast ion conductivity is stabilized in the low temperature region by the addition of a dopant such as Gd 2O 3.