Electrical conductivity of defect fluorite-type (Gd1−xYbx)2Zr2O7 solid solutions

(Gd1−xYbx)2Zr2O7 (0 ≤ x ≤ 1) solid solutions were prepared by pressureless-sintering process at 1973 K to investigate the substitution effect of Yb for Gd on their electrical properties. Electrical conductivity of (Gd1−xYbx)2Zr2O7 solid solutions were measured using complex impedance spectroscopy from 673 to 1173 K over a frequency range of 2 Hz to 2 MHz in air. (Gd1−xYbx)2Zr2O7 are oxide-ion conductor in the oxygen partial pressure range from 1.0 × 10−4 to 1.0 atm at all test temperature levels. The measured values of grain conductivity obey the Arrhenius relation. The grain conductivity of (Gd1−xYbx)2Zr2O7 increases with increasing temperature. However, the grain conductivity of (Gd1−xYbx)2Zr2O7 gradually decreases with increasing ytterbium content at identical temperature levels.