Sr-hexaferrite/maghemite composite nanoparticles—possible new mediators for magnetic hyperthermia

P. Veverka (1) , Emil Pollert (1) , K. Záveta (1) , Sébastien Vasseur (2) , Etienne Duguet (2)

1 Institute of Physics
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

Composite nanoparticles with variable ratios of M-type Sr-hexaferrite and maghemite phases were prepared via the sol–gel method employing polyvinylalcohol as the stabilizing agent, followed by thermal treatment at 600 °C for 32–190 min. The measurements in static magnetic field revealed considerable variation of the coercivity and remanence depending on the relative content of the highly magnetically anisotropic Sr-hexaferrite phase. Calorimetric heating experiments were carried out on aqueous gel suspensions under an alternating magnetic field of maximum amplitude Hmax = 15.1–68.4 kA m-1 and frequency ν = 108 kHz. They showed a strong dependence of the heating efficiency on the coercivity and remanence of the composites, with a specific absorption rate (SAR) value ranging from units to tens of W/g(Feferrimagnetic).

Mots clés: Hexaferrite; Maghemite; Composite nanoparticle; Hyperthermia; Magnetism

Domaines: Matériaux

P. Veverka, Emil Pollert, K. Záveta, Sébastien Vasseur, Etienne Duguet. Sr-hexaferrite/maghemite composite nanoparticles—possible new mediators for magnetic hyperthermia. Nanotechnology, 2008, 19 (21), 215705 (7 p.). ⟨10.1088/0957-4484/19/21/215705⟩. ⟨hal-00275871⟩