Investigation of Transport Properties of Pr Doped Cerium Oxide Nanoparticles as a Solid Electrolyte for IT-SOFC Applications

Pure and Pr doped CeO2 nanoparticles were synthesized by citrate-nitrate auto combustion method. The XRD patterns of the prepared nanoparticles were found to be polycrystalline nature having cubic fluorite CeO2 structure. SEM images depicted all the samples exhibited flaky and porous structure with few large aggregates. FT-Raman studies showed the suppression of F-2g peak in Pr doped CeO2 nanoparticles which indicated the increased oxygen vacancy concentration. UV-DRS spectra revealed the red shifting of absorption edge on Pr doping. The vibrational band assignment of pure and Pr doped CeO2 nanoparticles were analyzed by FT-IR spectroscopy. PL intensities of doped CeO2 nanoparticles decreased compared with pure CeO2 nanoparticles due to the evolution of non-radioactive oxygen vacancies in the structure. The variation of ionic conductivity as a function of temperature was studied using impedance spectroscopy for pure and Pr doped CeO2 nanoparticles. It was observed that the ionic conductivity of Pr doped CeO2 nanoparticles increased compared to pure CeO2 nanoparticles at the intermediate temperature.