Induction heating studies of magnetite nanospheres synthesized at room temperature for magnetic hyperthermia

An investigation of the synthesis of Fe3O4 nanopowders by the co-precipitation method is reported from aqueous and ethanol mediums. X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer are utilized to study the effect of variation of synthesis conditions on the crystal structure, crystallite size, microstructure and magnetic properties of the formed powders. The XRD analysis showed that the crystalline Fe3O4 phase was formed at Fe3+/Fe2+ molar ratio 2.0 prepared at room temperature for 1 h at pH 10. The crystallite size was in the range between 8 and 11 nm. TEM micrographs showed that the particles appeared as nanospheres. Superparamagnetic nanoparticles with low coercivity and remanence magnetization were achieved. Heating properties of the nanosphere samples in an alternating magnetic field at 160 KHz were evaluated. An excellent heating efficiency for the sample prepared in ethanol medium is a result of more relaxation losses occurring due to its small particle size.

► Magnetite nanopowders (∼8–11 nm) have been synthesized at room temperature.
► Magnetite particles was appeared as nanospheres.
► The saturation magnetization values were Ms=57.34 and 51.82 emu/g.
► SAR was reached (137.6 W/g) for sample synthesized in ethanol medium.
► Low Fe3O4 concentration suitable for hyperthermia.