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Selective Metal Exsolution in BaFe2-yMy(PO4)(2) (M = Co2+, Ni2+) Solid Solutionsстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 17 ноября 2015 г.
- Авторы: Alcover Ignacio Blazquez, Daviero-Minaud Sylvie, David Renald, Filimonov Dmitry, Huve Marielle, Paul Attfield J., Kabbour Houria, Mentre Olivier
- Журнал: Inorganic Chemistry
- Том: 54
- Номер: 17
- Год издания: 2015
- Издательство: American Chemical Society
- Местоположение издательства: United States
- Первая страница: 8733
- Последняя страница: 8743
- DOI: 10.1021/acs.inorgchem.5b01360
- Аннотация: The 2D-Ising ferromagnetic phase BaFe22+(PO4)(2) shows exsolution of up to one-third of its iron content (giving BaFe1.333+(PO4)(2)) under mild oxidation conditions, leading to nanosized Fe2O3 exsolved clusters. Here we have prepared BaFe2-yMy(PO4)(2) (M = Co2+, Ni2+; y = 0, 0.5, 1, 1.5) solid solutions to investigate the feasibility and selectivity of metal exsolution in these mixed metallic systems. For all the compounds, after 600 degrees C thermal treatment in air, a complete oxidation of Fe2+ to Fe3+ leaves stable M2+ ions, as verified by Fe-57 Mossbauer spectroscopy, TGA, TEM, microprobe, and XANES. The size of the nanometric alpha-Fe2O3 clusters coating the main phase strongly depends on the y(M) metal concentration. For M-rich phases the iron diffusion is hampered so that a significant fraction of superparamagnetic alpha-Fe2O3 particles (100% for BaFe0.5-xCo1.5(PO4)(2)) was detected even at 78 K Although Ni2+ and Co2+ ions tend to block Fe diffusion, the crystal structure of BaFe0.67Co1(PO4)(2) demonstrates a fully ordered rearrangement of Fe3+ and Co2+ ions after Fe exsolution. The magnetic behaviors of the Fe-depleted materials are mostly dominated by antiferromagnetic exchange, while Co2+-rich compounds show metamagnetic transitions reminiscent of the BaCo2(PO4)(2) soft helicoidal magnet.
- Добавил в систему: Филимонов Дмитрий Сергеевич