ELECTRICAL-TRANSPORT PROPERTIES OF CALCIUM ZIRCONATE AT HIGH-TEMPERATURE

Simultaneous measurements of electrical conductivity and thermoelectri c power of 1 mol% InO1.5 doped CaZrO3 were made at 1523, 1473, 1373 an d 1273 K under oxygen partial pressure, P-O2 between 10(-14) and 1 atm using dried O-2 + Ar and CO + CO2 gas mixtures. InO1.5 doped CaZrO3 w as found to be the hole-oxide ion mixed conductor under a dry atmosphe re. The partial conductivity of holes was predominant in the high P-O2 region and was proportional to P-O2(1/4). The partial conductivity of oxide ions without p(O2) dependency was predominant in the low p(O2) region. Partial thermoelectric powers of holes and oxide ions were the oretically evaluated from the total thermoelectric power measurements, and the electrical transport properties of holes, i.e. the mobility o f holes was estimated using so-called Jonker's analysis. The present r esults suggest the comparable concentration of holes with calcia stabi lized zirconia and the higher mobility of holes in CaZr0.99In0.01 O-2. 995. (C) 1998 Elsevier Science B.V. All rights reserved.