Oxide-ion conduction and dielectric relaxation in the fluorite-type Zr0.8Ln0.2O1.9 (Ln = Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu) system

The electrical conductivity and dielectric properties of the Zr0.8Ln0.2O1.9 (Ln = Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu) system which have a cubic fluorite-type structure were investigated in order to clarify a dynamic property of oxygen vacancy in oxide-ion conductors. The frequency dependences of dielectric constants (εr') were successfully explained by the superposition of Debye-type polarizations and electrolyte-electrode interfacial polarizations. The ac conductivity (σac) agreed with the calculated values using the dielectric parameters. It was found that the compositional dependence of dielectric properties was similar to that of σac.