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arXiv · 1506.00505

Evaluation of (BH)max and magnetic anisotropy of cobalt ferrite nanoparticles synthesized in gelatin

A. C. Lima·M. A. Morales·J. H. Araujo·J. M. Soares·D. M. A. Melo·A. S. Carrico
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Abstract

CoFe2O4 nanoparticles were synthesized using gelatin as a polymerizing agent. Structural, morphological and magnetic properties of samples treated at different temperatures were investigated by X-ray diffraction, scanning electron microscopy, Mossbauer spectroscopy and magnetization measurements. Our results revealed that the samples annealed at 623 K and temperatures above 973 K have a cation distributions given by (Co0.19Fe0.81)[Co0.81Fe1.19]O4 and (Co0.06Fe0.94)[Co0.94Fe1.06]O4, respectively. The particle sizes varied from 73 to 296 nm and the magnetocrystalline anisotropy, K1, has values ranging from 2.60x10^6 to 2.71x10^6 J/m3, as determined from the law of approach to saturation applied to the MxH data at high field. At 5 K, the saturation magnetization, coercive field and (BH)max varied from 76 to 95 Am2/kg, 479.9 to 278.5 kA/m and 9.7 to 20.9 kJ/m3, respectively. The reported values are in good agreement with near-stoichiometric cobalt ferrite samples.

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A. C. Lima, M. A. Morales, J. H. Araujo, J. M. Soares, D. M. A. Melo, A. S. Carrico. 2015-06-01. Evaluation of (BH)max and magnetic anisotropy of cobalt ferrite nanoparticles synthesized in gelatin. https://doi.org/10.1016/j.ceramint.2015.05.148

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