Influence of copper cations on the magnetic properties of NiCuZn ferrite nanoparticles

Ni0.6−xCuxZn0.4Fe2O4 (x=0–0.5) ferrite nanoparticles were prepared, employing a reverse micelle process. X-ray diffraction and transmission electron microscopy evaluations demonstrated that single phase spinel ferrites with narrow size distribution were obtained. Vibrating sample magnetometer was employed to probe the magnetic properties of the samples. It was found that with an increase in copper content, the saturation magnetization decreases. Magnetic dynamics of the samples was studied by measuring a.c. magnetic susceptibility versus temperature at different frequencies. The phenomenological Néel–Brown and Vogel–Fulcher models were employed to distinguish between the interacting or non-interacting systems. The system exhibits that there is strong interaction among fine particles.

Research highlights► Fine particles of Ni0.6−xCuxZn0.4Fe2O4 (x=0–0.5) with narrow distribution size were prepared by reverse micelle method. ► The ferrites were fabricated at a relatively low temperature compared to the other synthesizing process of magnetic nanoparticles. ► The saturation magnetization of nanoparticles decreased with an increase in copper amount. ► Fitting the experimental data of susceptibility with the Vogel–Fulcher model confirms the existence of strong interactions between nanoparticles.