Dielectric relaxation properties of nanostructured Ce<inf>0.8</inf>Gd <inf>0.1</inf>Pr<inf>0.1</inf>O<inf>2-δ</inf> material at intermediate temperatures

The dielectric relaxation behavior of the fluorite structured nanocrystalline Ce0.8Gd0.1Pr0.1 O 2-δ compound was studied in the temperature range of 200-550 °C. Two different types of relaxation processes were observed corresponding to (1) defect pairs such as (Pr′Ce - VO) and (Gd′Ce - VO) and (2) the trimers such as (Pr′Ce - VO - Gd′Ce). The correlation between ionic conduction and the dielectric properties of the nanocrystalline material is discussed. Very low values of the migration energy and association energy of the oxygen vacancies are observed, which are 0.42 and 0.03 eV, respectively. The obtained value of association energy agrees well with the theoretical prediction on doubly doped ceria. © 2009 American Institute of Physics.