Structural and magnetic investigations of Cr substituted NiFe2O4 nanostructures

Ultrafine nanocrystalline Chromium (Cr) substituted Nickel Ferrites with general formula of NiCrxFe2-xO4 (0 ≤ x ≤ 1) have been made with co-precipitation method. Structure and phase of synthesized nanoparticles were identified by X-ray diffraction (XRD). The results assure for formation of single phase cubic spinel structure with Fd3m symmetry. Increasing trend in X-ray densities due to decrease in lattice parameter has been observed with increasing Cr concentration in NiFe2O4. Morphology of synthesized nanoparticles were analysed with field emission scanning electron microscope (FE-SEM) and it has been observed that nanoparticles were dense and evenly distributed over the whole surface. Room temperature and low temperature magnetic measurements were investigated with physical property measurement system (PPMS). It has been found that magnetic coercivity was boosted with Cr substitution at level x = 1 with decreasing trend in saturation magnetization at room temperature. However, low temperature magnetic analyses for x = 1 showed increase in saturation magnetization and coercivity with decrease in ambient temperature.