Preparation and Investigation of Compounds with the 114-Type Structure in the Y-Sc-Ba-Co-O System
Научная публикация
| Общая информация |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
Опубликована,
Оригинальность:
Переводная
|
| Журнал |
Journal of Structural Chemistry
ISSN: 0022-4766
, E-ISSN: 1573-8779
|
| Вых. Данные |
Год: 2020,
Том: 61,
Номер: 1,
Страницы: 29-43
Страниц
: 15
DOI:
10.1134/S0022476620010047
|
| Ключевые слова |
cationic substitutions; ceramics; cobaltates; crystal structure; phase formation; Sc; single crystals |
| Авторы |
Kameneva M.Y.
1
,
Kozeeva L.P.
1
,
Lavrov A.N.
1
,
Komarov V.Yu.
1,2
,
Podberezskaya N.V.
1
,
Kuchumov B.M.
1
,
Rudina N.A.
3
|
| Организации |
| 1 |
Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russian Federation
|
| 2 |
Novosibirsk State University, Novosibirsk, Russian Federation
|
| 3 |
Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russian Federation
|
|
The processes of phase formation in the Y-Ba-Co-O system doped with scandium are studied in the region of compositions 1:1:4:7. The mechanism of interaction of initial reagents changes with scandium concentration: at low scandium contents, the (Y1−yScy)BaCo4O7+x (R114) doped oxide is formed, similarly to the undoped system, through the YBaCo2O5+x (R112) phase; at significantly higher scandium contents (≥0.2), the role of the intermediate and the competing phase is played by BaCo1−yScyO3−x representing a number of solid solutions which are stable in wide ranges of temperatures and scandium contents. It is shown that scandium in the R114 structure preferably occupies the yttrium position (Y1−yScyBaCo4O7+x), and the maximum degree of substitution is ymax ≈ 0.3–0.35. When yttrium is substituted with a smaller (in terms of ionic radii) scandium atom, the size of the unit cell diminishes nearly isotropically, the maximum change of its volume being 2.0% (from 353.0 Å3 to 345.9 Å3). © 2020, Pleiades Publishing, Ltd.