Electrical conductivities of CaO doped ZrO2-CeO2 solid solution system

Electrical conductivities, sigma, of (Zr1-xCexO2)(0.9)(CaO)(0.1) (x = 0.1-1 .0) were investigated by a D.C. four terminal technique at 1173-1573 K as a function of the oxygen partial pressure from 10(-15) to 1 atm. In the regi on of x = 0.4-1.0, the electrical conductivity is separated into the ionic and electronic conductivity by using the relation of sigma = sigma (ion) sigma (0)(e) P-O2(-1/4). The electrical conduction at Po, = I atm is essent ially ionic. The composition dependence of the electronic conductivity show s opposite tendency to that of the ionic conductivity, that is, the electro nic conductivities increase with the increase in CeO2 content (x) and show a maximum at x similar or equal to 0.6, then decrease with x while the ioni c conductivity behaves vice versa, In the CaO doped ZrO2-CeO2 system, the f ormation of the solid solution results in the low ionic and high electronic conduction. (C) 2001 Elsevier Science B.V. All rights reserved.