ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 37, Number 4
JKCSEZ 37(4)
August 20, 1993 

The x values and electrical conductivities of the nonstoichiometric compounds CeO2-x have been measured in a temperature range from 600 to 1200℃ under oxygen partial pressure of 2 × 10-1 ∼ l × l0-4 atm. The enthalpy of the defect formation shows an endothermic process with the oxygen partial pressure dependence (1/n value) of -1/3.18 ∼ -1/3.69. The activation energy and 1/n value for the electrical conductivity are estimated as 1.75 eV and -1/4, respectively. According to the x values, the σ values, and the thermodynamic data, the defect structure of the ceria seems to be the formation of singly charged negative oxygen vacancies. The n-type semiconducting behaviors could be explained by the presence of excess metals in the lattice as the conduction electron donor.