Solid Solubility, Raman Spectra and Electrical Property of the Solid Solutions Ce 1‐x Nd x O 2‐δ by Sol‐gel Route

Ce 1‐x Nd x O 2‐δ ( x = 0.05–0.55) solid solutions prepared by sol‐gel route were crystallized in a cubic fluorite structure. The solid limit was determined to be as high as x = 0.45. Raman spectra of the solid solutions with lower composition exhibited only one band, which was assigned to F 2g mode. Increasing composition produced broad and asymmetric F 2g mode with an appearance of low frequency tail. The new broad peak observed at higher frequency side of the F 2g mode associated with the oxygen vacancy in the lattice. The impedance spectra of the solid solutions showed definitely ionic conduction, and Ce 0.80 Nd 0.20 O 2‐δ solid solution possessed a maximum conductivity. At 500 °C, the conductivity and activation energy were 2.65 × 10 −3 S/cm and 0.82 eV, respectively.