2551905
doi
10.3897/j.moem.4.1.33270
oai:zenodo.org:2551905
Thermally stimulated oxygen desorption in Sr2FeMoO6-δ
Kalanda, Nikolay A.
Scientific-Practical Materials Research Centre of NAS of Belarus, Minsk, Belarus
info:eu-repo/semantics/openAccess
Creative Commons Attribution 4.0 International
https://creativecommons.org/licenses/by/4.0/legalcode
strontium ferromolybdate
oxygen nonstoichiometry
defect formation
oxygen desorption
<p>Polycrystalline Sr<sub>2</sub>FeMoO<sub>6-δ</sub> specimens have been obtained by solid state synthesis from partially reduced SrFeO<sub>2,52</sub> and SrMoO<sub>4</sub> precursors. It has been shown that during oxygen desorption from the Sr<sub>2</sub>FeMoO<sub>6-δ</sub> compound in polythermal mode in a 5%H<sub>2</sub>/Ar gas flow at different heating rates, the oxygen index 6-δ depends on the heating rate and does not achieve saturation at T = 1420 K. Oxygen diffusion activation energy calculation using the Merzhanov method has shown that at an early stage of oxygen desorption from the Sr<sub>2</sub>FeMoO<sub>6-δ</sub> compound the oxygen diffusion activation energy is the lowest Е<sub>а</sub> = 76.7 kJ/mole at δ = 0.005. With an increase in the concentration of oxygen vacancies, the oxygen diffusion activation energy grows to Е<sub>а</sub> = 156.3 kJ/mole at δ = 0.06. It has been found that the dδ/dt = f (Т) and dδ/dt = f (δ) functions have a typical break which allows one to divide oxygen desorption in two process stages. It is hypothesized that an increase in the concentration of oxygen vacancies V<sub>o</sub><sup>••</sup> leads to their mutual interaction followed by ordering in the Fe/Mo-01 crystallographic planes with the formation of various types of associations.</p>
NUST MISiS
2018-05-01
info:eu-repo/semantics/article
2551904
1579527634.996045
36286
md5:0d431b1b540327ac5ed83fe1393dd4f8
https://zenodo.org/records/2551905/files/MoEM_article_33270.xml
668783
md5:9f79f2307723b72993f4809b7991eea4
https://zenodo.org/records/2551905/files/MoEM_article_33270.pdf
public
Modern Electronic Materials
4
(1)
1-5
2018-05-01