LAUSR

Abstract Sr-doped lanthanum manganite La0.95Sr0.05MnO3+δ powder was obtained by sol-gel method. The effect of heating behavior and the effect of interstitial oxygen on structural properties of the LSMO ceramics were studied by XRD, including high-temperature in situ measurements (150–6500С). The as prepared powder is single-phase and has a rhombohedral structure (R-3c space group). In situ XRD results showed that heating under vacuum does not lead to a structure change; which remains rhombohedral. However, with an increase of temperature, the lattice parameters increase, reflecting a decrease of interstitial oxygen fraction. In addition, rhombohedral angle α decreases, which indicates that the lattice tends to cubic. Comparison of the studied sample with the La0.95Sr0.05MnO3 annealed in vacuum under special conditions has been carried out. Thermal stability of the material under heating and vacuum, which did not lead to the expected phase transition, was revealed. The necessary conditions for obtaining oxygen stoichiometry are given in work.