Cubic structured core/shell NiFe2O4@ZnFe2O4 nanocomposite: Structural, morphological and magnetic properties

Double ferrite nanocomposites with NiF2O4 as the core and ZnFe2O4 as the shell, were synthesised through combination of co-precipitation and hydrothermal methods. This two-step process resulted in formation of a cubic structured core of around 100 nm and a shell of zinc ferrite nanoparticles which are below 10 nm in size. The core/shell structures were characterised using various techniques such as XRD, Raman, TEM/EDS and VSM. In addition, Ni leaching out of these structures was tested in the ultra-pure water and saline solution. These analyses demonstrated that the shell of zinc ferrites effectively prevents Ni leaching from the core keeping the concentration of nickel well below the level usually found in drinking water. These core/shell nanocomposites exhibit a ferrimagnetic behaviour.