Self-diffusion of oxygen in La1-xSrxFeO3-δ

The perovskite-type system La1-xSrxFeO3-delta is a candidate material for electrodes in magnetohydrodynamic generators, fuel cells and electrocatalysts. Various effects of the material, including defect structures, have been studied in relation to their electrical properties. It is very useful to determine the oxygen-ion diffusion coefficient of the material for the purpose of understanding such defect structures. Diffusion data of polycrystals of this system over the composition range were obtained, and possible defect structures were explained in relation to these and other data. It was found that the behaviour of the volume diffusion coefficient is strongly influenced by the diffusion property of the end compositions (x = O and 1.0). The diffusion coefficient at x = 0.6 behaves like that at x = 1.0; on the other hand, at x = 0.4, it behaves like that at x = O. 8 refs.