In Situ Investigation of Structural Changes in Perovskite-Like Oxides Based on Lanthanum Ferrite in Media with Different Partial Pressures of Oxygen
Bulletin of the Russian Academy of Sciences: Physics
, E-ISSN: 1934-9432
Boreskov Institute of Catalysis SB RAS
In situ high temperature X-ray diffraction is used to study structural changes in perovskite-like oxides (La, Sr)Fe0.7Ni0.3O3 at 900°C in media with different partial pressures of oxygen. It is shown that when the partial pressure of oxygen is varied, samples undergo relaxation of structure in the form of an increase in the volume of an elementary cell, due to the volume diffusion of oxygen. A model for this process is proposed, and the diffusion coefficients of oxygen are estimated.