Investigations on the enhancement of thermomagnetic properties in Fe2.4Ga0.6O4

ABSTRACT The structural, magnetic and calorimetric properties of Fe2.4Ga0.6O4 nanoferrite have been investigated. X-ray and neutron diffraction coupled analyses using Rietveld refinements have shown that the samples under investigation, obtained by different bottom-up methods, crystalize with a cubic structure in the space group (N° 227). The Ga3+ ions preferentially occupying the tetrahedral sublattice of the inverse spinel partly screen the dipole–dipole interactions and lead to the reduction of the magnetic response of Fe3+ ones. Calorimetric measurements confirm that the nanosized Fe2.4Ga0.6O4 system weakly agglomerates and simultaneously collect and release optimal amount of heat under the influence of an alternating magnetic field with the 15.3 kA/m of maximum magnetic field strength and 532 kHz of frequency. The values of the specific absorption coefficients obtained for gallium ferrites, similar to those typical for cobalt ferrites used commercially in biomedicine, together with very low superparamagnetic blocking temperature validated by Mössbauer spectroscopy analysis, make the system an attractive therapeutic material.