The effect of A-site cation (Ln = La, Pr, Sm) on the crystal structure, conductivity and oxygen reduction properties of Sr-doped ferrite perovskites
By Ren, Yaoyu; Küngas, Rainer; Gorte, Raymond J. & Deng, Changsheng
Published in Solid State Ionics
2012
Abstract
The influence of A-site cation (Ln = La, Pr, Sm) on the crystal structure of Sr-doped ferrite perovskites (Ln0.8Sr0.2FeO3 − δ, LnSF) was studied and the results used to interpret the differences in electronic conductivity. The electronic conductivity decreased with decreasing A-site cation radius, i.e. in the order La > Pr > Sm between 573 K and 1173 K, whereas the ionic conductivity increased in the order La < Sm < Pr between 923 K and 1073 K. The ionic conductivity of Pr0.8Sr0.2FeO3 − δ (PSF) was more than one order of magnitude higher than that of La0.8Sr0.2FeO3 − δ (LSF) at 973 K.