Magnetic heating by cobalt ferrite nanoparticles

P. Veverka (1) , M. Veverka (1) , O. Kaman (1) , A. Lancok (1, 2) , K. Záveta (1) , Emil Pollert (1) , Karel Kní?ek (1) , J. Boháček (2) , M. Benes (3) , Petr Ka?par (4) , Etienne Duguet (5) , Sébastien Vasseur (5)

1 Institute of Physics
2 Institute of Inorganic Chemistry
3 IMC / CAS - Institute of Macromolecular Chemistry of the Czech Academy of Sciences
4 FEL CTU - Faculty of Electrical Engineering [Prague]
5 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

In the quest for suitable materials for hyperthermia we explored the preparation and properties of nanoparticles of Co ferrite. The material was produced by coprecipitation from water solution of Co and Fe chlorides and afterwards annealed at 400, 600 and 800 °C. The resulting particles were characterized by XRD, TEM, Mössbauer spectroscopy, and dc and ac magnetometry. The heating experiments in ac magnetic fields of various amplitudes were performed with diluted systems of particles suspended in agarose gel and the results were interpreted on the basis of the ac magnetic losses measured at various temperatures. The increase of magnetic losses and consequently of the heating efficiency with increasing temperature is explained by the strong dependence of the constant of magnetocrystalline anisotropy of Co ferrite on temperature.

Mots clés: Nanoparticles; Cobalt; Ferrite; Magnetism

Domaines: Matériaux

P. Veverka, M. Veverka, O. Kaman, A. Lancok, K. Záveta, et al.. Magnetic heating by cobalt ferrite nanoparticles. Nanotechnology, 2007, 18 (34), 345704 (7 p.). ⟨10.1088/0957-4484/18/34/345704⟩. ⟨hal-00175597⟩