ELECTRICAL-CONDUCTIVITY OF THE SOLID-SOLUTIONS X ZRO2+(1-X) YB2O3 0.01-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.09

ZrO2-doped Yb2O3 solid solutions containing 1, 3, 5, 7 and 9 mol% ZrO2 were synthesized from spectroscopically pure Yb2O3 and ZrO2 powders and found to be rare earth C-type structure by XRD technique. Electrical conductivities were measured as a function of temperatures from 700 to 1050-degrees-C and oxygen partial pressures from 1 X 10(-5) to 2 x 10(-1) atm. The electrical conductivities depend simply on temperature and the activation energies are determined to be 1.56-1.68 eV. The oxygen partial pressure dependence of the electrical conductivity shows that the conductivity increases with increasing oxygen partial pressure, indicating p-type semiconductor. The P(O2) dependence of the system is nearly Power of 1/4. it is suggested from the linearity of the temperature dependence of electrical conductivity and only one value of 1/n that the solid solutions of the system have single conduction mechanism. From these results, it is concluded that the main defects of the system are negatively doubly charged oxygen interstitial in low. ZrO2 doping level and negatively triply charged cation vacancy in high doping level and the electrical conduction is due to the electronic hole formed by the defect structure.