Influence of lanthanide impurities on the anion conductivity of cubic zirconia

The ion conductivity of ceramics based on cubic zirconia with lanthanide impurities has been investigated using impedance spectroscopy. Ambiguous behavior of activation energy of anion migration in this material has been found. At a high experimental temperature (770$^\circ$C), the activation barrier for anion migration decreases as the ionic radius of the cation impurity increases, while at a low temperature (380$^\circ$C), an increase in this quantity is observed. A simple elastic model of the migration barrier of the anion in the crystallite, which confirms the experimental results at a high temperature, has been considered.