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arXiv · 1103.3786

Magnetic properties and energy absorption of CoFe2O4 nanoparticles for magnetic hyperthermia

T. E. Torres·A. G. Roca·M. P. Morales·A. Ibarra·C. Marquina·M. R. Ibarra·G. F. Goya
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Abstract

We have studied the magnetic and power absorption properties of three samples of CoFe2O4 nanoparticles with sizes from 5 to 12 nm prepared by thermal decomposition of Fe (acac)3 and Co(acac)2 at high temperatures. The blocking temperatures TB estimated from magnetization M(T) curves spanned the range 180 < TB < 320 K, reflecting the large magnetocrystalline anisotropy of these nanoparticles. Accordingly, high coercive fields HC \approx 1.4 - 1.7 T were observed at low temperatures. Specific Power Absorption (SPA) experiments carried out in ac magnetic fields indicated that, besides particle volume, the effective magnetic anisotropy is a key parameter determining the absorption efficiency. SPA values as high as 98 W/g were obtained for nanoparticles with average size of \approx12 nm.

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T. E. Torres, A. G. Roca, M. P. Morales, A. Ibarra, C. Marquina, M. R. Ibarra, G. F. Goya. 2011-03-19. Magnetic properties and energy absorption of CoFe2O4 nanoparticles for magnetic hyperthermia. https://doi.org/10.1088/1742-6596/200/7/072101

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