Ionic Conductivity of Calcia, Yttria, and Rare Earth‐Doped Cerium Dioxide

Electrical conductivity specimens of and were prepared by a cast ceramic tape technique and by the more conventional method of isostatically pressing and sintering. The electrical conductivity of these specimens was measured in oxygen between 400°–1000°C. In this region the conduction is essentially ionic, and the temperature dependence of the electrical conductivity, , was represented by the following second degree equation where and . Lower valent dopant cations with smaller ionic radii than Ce +4 exhibited a larger activation energy than cations with larger ionic radii than Ce +4 . The magnitude of the electrical conductivity was not very dependent on either the type of dopant or the method of sample preparation.