Synthesis, structure and conductivity studies of co-doped ceria: CeO2−Sm2O3−Ta2O5 (Nb2O5) solid solution

Abstract

We report the synthesis, structure and conductivity of a new series of Sm and Ta/Nb doped ceria compounds. Laboratory powder X-ray diffraction (PXRD) data show that these compounds possess the fluorite structure. The formation of a pure phase is controlled by the Sm:Ta(Nb) ratio. The conductivities in the series Ce0.9−xSmx(Ta/Nb)0.1O2.05−0.5x have been measured by ac impedance spectroscopy and were found to be of the order of 10−4/10−5Scm−1 at 550°C.