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In this study, crystalline nanoparticles CoFe2O4 with a spinel structure were prepared by hydrothermal methods. The magnetic properties of non-calcined cobalt ferrite formed from nanocrystalline powders. The dependence of the particle size and crystalline structure of obtained nanoparticles in the synthesis conditions was examined and characterized using field emission scanning electron microscope (FESEM), and X-ray diffraction analysis (XRD). The XRD analysis revealed a high degree of crystallinity and confirmed the spinel structure of crystalline nanoparticles CoFe2O4. The FESEM image shows the presence of spherical ferrite particles with an average diameter of about 13-18 nm. The results also show that the formation of cobalt ferrite spinel structures was affected by fabrication conditions. Magnetic hysteresis loop data confirm that the magnetic properties of nanoparticles depend on the synthesis conditions. The material prepared by the hydrothermal route and calcination at 150ºC with molar ration Co2+: Fe3+ = 1:2.2 for 2 hours has higher magnetic saturation than that of the surveyed samples.
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