Speaker
Dr
Uliana Ancharova
(ISSCM SB RAS)
Description
Depending on substitution degree and external conditions strongly-nonstoichiometric strontium ferrites have certain features of the local structure [1-3]. It is related to extremely high amount of oxygen vacancies, laying beyond the homogeneity region of perovskite or any of vacancy-ordered phases. That vacancy concentration tend to be adopted by the structure through formation of local ordering of the vacancies and phase separation with forming nano-heterogeneous structures inside the perovskite matrix. Ion-transport functional properties of nano-heterogeneous materials are primarily related to their local structure, which differ from the structure averaged over the entire crystal.
*In situ* XRD experiments show the transformation of the structure under low oxygen partial pressure at different temperatures (up to 900ºC). Phase composition and structure parameters are in strong correlation to equilibrium oxygen content at different environment conditions.
X-ray diffraction experiments were carried out with involvement of equipment belonging to the shared research center SSTRC, BINP SB RAS.
[1] U.V. Ancharova, Domain structure investigation of strontium ferrites/cobaltites // Powder Diffraction Journal - 2013. - 28. - S2. - P.S51-S64.
[2] U.V. Ancharova, S.V. Cherepanova, Nano-domain states of strontium ferrites SrFe1−yMyO2.5+x (M=V, Mo; y≤0.1; x≤0.2) // Journal of Solid State Chemistry, - 2015. - V.225. - P.410-416.
[3] У.В. Анчарова, С.В. Черепанова, С.А. Петров, Способы адаптации высокой концентрации кислородных вакансий в нестехиометрических ферритах стронция // Журнал Структурной Химии, - 2016. - in press.
Primary author
Dr
Uliana Ancharova
(ISSCM SB RAS)
Co-authors
Dr
Svetlana Cherepanova
(BIC SB RAS)
Zakhar Vinokurov
(BIC SB RAS)
