ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 30, Number 1
JKCSEZ 30(1)
February 20, 1986 

Electrical conductivities of NiO-Y2O3 systems containing 0.8, 1.6, and 3.2 mol% NiO have been measured in the temperature range of 400 to 1100℃ at PO2's of 1 × 10-5 to 2 × 10-1 atm. Plots of logσ vs 1/T at constant PO2's are found to be linear with an inflection at temperature around 650℃. The slopes are steeper in the high temperature region above 650℃ than in the low temperature region below 650℃. The average activation energies are 41.8kcal/mol in the high temperature region and 12.5kcal/mol in the low temperature region. PO2's dependence value, 1/n, is 1/5.1∼1/5.4 in the high temperature region and 1/5.9∼1/6.2 in the low temperature region. The NiO-Y2O3 systems are found to be an electronic p-type semiconductor. The predominant defects in the systems are believed to be triply ionized yttrium vacancy in the high temperature region and doubly ionized oxygen interstitial in the low temperature region. Ionic contribution to the total conductivity is found from σ∝PO2 in the temperatures below 650℃.