Facile approach for synthesis of high moment Fe/ferrite and FeCo/ferrite core/shell nanostructures

In the present study, we developed a facile approach for synthesis of high magnetic moment monodisperse Fe/ferrite and FeCo/ferrite core/shell nanoparticles. Fe3O4 and CoFe2O4 nanoparticles were at first synthesized through sonochemical process, followed by thermal annealing in presence of hydrogen (H2) gas for 2h for reduction into Fe and FeCo nanoparticles, respectively. Then, oxidation of Fe and FeCo nanoparticles up to 48h in air atmosphere resulted in complete formation of Fe/ferrite and FeCo/ferrite core/shell nanostructures. Different analytical techniques such as X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy and vibrating sample magnetometer were used to characterize and confirm the successful formation of the core/shell nanostructures. In view of the obtained high magnetic Fe or FeCo core and biocompatible ferrite shell, these core-shell Fe/ferrite and FeCo/ferrite nanoparticles are expected to be promising materials for various bio-sensing applications.