Structural, Morphological and Magnetic Properties of FeCo-(Fe,Co)3O4 Nanocomposite Synthesized by Proteic Sol-Gel Method Using a Rotary Oven

FeCo nanoparticles coated with (Fe,Co)(3)O-4 (magnetite doped with cobalt) were synthesized by the proteic sol-gel chemical route. The synthesized materials were characterized by Thermogravimetry (TG), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), vibrating-sample magnetometer (VSM) and Mossbauer spectroscopy (MS). The results show that the increase in temperature and the choice of the correct air/N-2 flow directly influence on the final physical-chemical properties of the nanocomposite. The SEM and TEM images confirmed that a thin layer of oxide was formed on the alloy, indicating that it was obtained a self-assembled FeCo-(Fe,Co)(3)O(4 )nanocomposites. In addition, the VSM results show that a possible exchange-spring coupling in magnetic FeCo-(Fe,Co)(3)O-4 nanoparticles occurred with high saturation magnetization from FeCo alloy and high coercivity from (Fe,Co)(3)O-4. The rotary oven allows the uniform contact of the powder with the atmosphere of synthesis during the different oxidation-reduction steps, generating more homogeneous particles.