Measurement of chemical diffusion coefficient and surface exchange on mixed ionic electronic conductors using periodical pO2 oscillations

A new method for estimation of transport parameters in mixed ionic electronic conductors (MIEC) is proposed. Microscopic diffusion and surface exchange coefficients have been obtained with a dynamic conductivity analysis. The estimation of diffusion coefficient of interstitial oxygen and the surface exchange coefficient for well known compositions La2NiO4 and La2CuO4 shows very good agreement with SIMS data reported in the literature. The novel characterization turns out to be a time saving method which allows the precise estimation of diffusion and surface exchange coefficients in mixed conductors.