Europium valence state in europium monoxide-iron (Cobalt) magnetic composites

• Published in: Russian journal of inorganic chemistry Vol. 54; no. 10; pp. 1517 - 1521
• Main Authors: Ignat’eva, N. I., Shkvarin, A. S., Osotov, V. I., Finkel’shtein, L. D.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-10-2009
• Subjects: Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Synthesis and Properties of Inorganic Compounds; Valence State; Europium Oxide; Trivalent Europium; Ferromagnetic Semiconductor; Magnetic Composite
• ISSN: 0036-0236; 1531-8613
• DOI: 10.1134/S0036023609100027

Composite magnetic powders EuO/Fe(Co) were synthesized. These composites are candidates for use as materials for spintronics devices operating at room temperature. The composites synthesized by carbothermal reduction of oxide mixtures Eu
2
O
3
and Fe
2
O
3
(or Co
3
O
4
) contain not only europium in the main valence state (2+) but also europium in the state 3+, its content increasing with the content of the
d
metal and depending on technological parameters of the reduction process. The content of the trivalent europium in the composites was estimated by chemical analysis and
L
111
-edge X-ray absorption spectroscopy (XAS). The results obtained by these methods correlate with each other. XAS is considered to be a quantitative express method of certification of materials containing europium in various valence states.