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

TL;DR

This study investigates the structural, morphological, and magnetic properties of cobalt ferrite nanoparticles synthesized with gelatin, revealing how annealing temperature influences their cation distribution, particle size, magnetic anisotropy, and magnetic performance.

Contribution

It provides new insights into how synthesis temperature affects the properties of gelatin-derived cobalt ferrite nanoparticles, including magnetic anisotropy and maximum energy product.

Findings

Particle sizes ranged from 73 to 296 nm.

Magnetocrystalline anisotropy K1 ranged from 2.60x10^6 to 2.71x10^6 J/m3.

(BH)max varied from 9.7 to 20.9 kJ/m3.

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.