Superparamagnetism of Co-Ferrite Nanoparticles
نویسنده
چکیده
Well-defined CoFe2O4 nanoparticles embedded in amorphous SiO2 matrix have been synthesized by sol-gel method, characterized and investigated by Mössbauer spectroscopy and magnetic measurements. The mean particle size was found to increase from 3 to 15 nm by varying the temperature of a subsequent annealing from 800 to 1100 ◦C. The composites exhibited superparamagnetic behavior with the blocking temperature increasing with the mean particle size. The frequency dependent AC susceptibility was found to obey the Néel Arrhenius law. Both observations are compatible with a model of non-interacting randomly oriented single-domain particles.
منابع مشابه
Synthesis and Properties of Polymer Nanocomposites with Tunable Electromagnetic Response
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