Fe1-yO nanoparticles: organometallic synthesis and magnetic properties.
Non-stoichiometric wüstite particles (Fe(1-y)O) are synthesized using the controlled room-temperature hydrolysis of the organometallic precursor {Fe[N(SiMe3)2]2}. Particles stabilized by hexadecylamine with a diameter of approximately 5 nm are obtained. For such small nanoparticles, a distorted crystallographic structure is evidenced by wide-angle X-ray scattering at room temperature and reported for the first time. The study of the magnetic properties indicates that these particles are composed of an antiferromagnetic core surrounded by a ferromagnetic shell. According to the Néel theory, we demonstrate that this shell consists of 1.5 % of Fe3+ ions ferromagnetically coupled with Fe2+ ions.
Glaria
Arnaud
A
Laboratoire de Chimie de Coordination, UPR8241 CNRS, 205 route de Narbonne, 31077 Toulouse Cedex, France.
Kahn
Myrtil L
ML
Lecante
Pierre
P
Barbara
Bernard
B
Chaudret
Bruno
B