Oxygen release technique: Ba0.5Sr0.5(Co0.8Fe0.2)0.85Ta0.15O3-δ

The work is related to the development of novel oxygen release technique to obtain continuous phase diagrams of oxides with mixed ionic-electronic conductivity. Promising perovskite-like composition Ba0.5Sr0.5(Co0.8Fe0.2)(0.85)Ta0.15O3-delta (BSCFT15) was chosen as a sample. As-prepared samples of BSCFT15 was studied by means of X-Ray diffraction analysis and scanning electron microscopy. Continuous equilibrium phase "3-delta - lg pO(2) - T" diagram obtained by oxygen release technique is presented for the composition BSCFT15 for the first time. The diagrams allowed us to detect the new phase transition P-1 (low temperature phase, Pm-3m) - P-2 (high-temperature phase, Fm-3c). (C) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the III All-Russian Conference (with International Participation) "Hot Topics of Solid State Chemistry: From New Ideas to New Materials'.