Structure, Ionic Transport Properties and Scaling Behavior of Eu, Pr, and Sm Co-Doped Ceria Oxygen Ion Conductors

摘要

In this work, structural, electrical, and scaling behavior of Eu, Pr, and Sm co-doped ceria-based ionic conductors are reported. The materials are prepared using citrate-auto ignition method. The average particle size is found to be within 20 nm. The values of lattice parameter are found to depend on the ionic radius of dopants. Sm-Eu co-doped ceria shows the highest conductivity and lowest activation energy for the conduction. Pr-Sm co-doped ceria shows highest and Sm-Eu co-doped ceria shows lowest migration energy. The values of dc conductivity are found to be consistent with the charge carrier concentration. The relaxation phenomenon is investigated using Cole-Davidson formalism. The scaling behavior of complex impedance plots, impedance and modulus spectra confirm the temperature and dopant-independent conduction and relaxation mechanism. The impact of multivalency of Pr on conductivity and relaxation is also discussed.