The chemical diffusion and surface exchange coefficients were measured for SrFeO3–δ, La0.5Sr0.5FeO3–δ, and La0.2Sr0.8Cr0.2Fe0.8O3–δ at 790 to 1000C and PO2 = 0.01 to 1atm by electrical conductivity relaxation. Values of the chemical diffusion and surface exchange coefficients were obtained by monitoring the variation of electrical conductivity after an abrupt change in O partial pressure. The vacancy diffusion coefficient (Dv), oxygen ion self-diffusion coefficient and surface exchange coefficients at thermal equilibrium were calculated by using the measured thermodynamic factors and were compared with literature data for other compositions.

Oxygen Transport Kinetics in SrFeO3- δ, La0.5Sr0.5FeO3- δ and La0.2Sr0.8Cr0.2Fe0.8O3- δ Measured by Electrical Conductivity Relaxation. J.Yoo, A.Verma, S.Wang, A.J.Jacobson: Journal of the Electrochemical Society, 2005, 152[3], A497-505