Preparation and Properties for Solid Solution Ce0.8Pr0.2-xNdxO2-δ(x=0.02, 0.05, 0.1)

Ce_0.8Pr_0.2–xNd_xO_2-δ(x = 0.02, 0.05, 0.1) solid solutions were synthesized by the sol-gel method. The XRD results show that all powders calcined at 800 °C are crystallized in a single cubic fluorite structure. The average grain sizes are between 20 nm and 25 nm. The Raman spectra analysis reveals that the solid solution Ce_0.8Pr_0.2–xNd_xO_2-δ has a cubic fluorite structure with oxygen vacancies. The oxygen vacancy concentration is increased by doping Nd in Ce_0.8Pr_0.2–xNd_xO_2-δ. Impedance spectra shows that the conductivity of rare earth co-doped ceria Ce_0.8Pr_0.18Nd_0.02O_2-δ is higher than that of single rare earth doped ceria Ce_0.83Sm_0.17O_2−y. The results also show that Ce_0.8Pr_0.18Nd_0.02O_2-δ possess maximum conductivity. At 600 °C, the conductivity is 1.85×10^-2S/cm, which is assigned to the higher oxygen vacancy concentration and the hopping electron transition of small polarons in the sample Ce_0.8Pr_0.18Nd_0.02O_2-δ.