Temperature-programmed C18O2 SSITKA for powders of fast oxide-ion conductors: Estimation of oxygen self-diffusion coefficients

Abstract For powders of oxide-ion conductors based on Al/Fe- doped lanthanum silicates as well as Sc+Ce-doped zirconia, the temperature –programmed exchange with C 18 O 2 in the SSITKA mode was applied for estimation of the oxygen self-diffusion coefficients D o . Comparison with results obtained for dense ceramics of these electrolytes using SIMS isotope profiling and conductivity measurements demonstrated a reasonable agreement for powders sintered at high temperatures, thus providing required verification of C 18 O 2 SSITKA approach. For powders calcined at moderate temperatures much lower values of D O were obtained thus suggesting a strong negative effect of inhomogeneity of dopants spatial distribution on the oxygen mobility.