SYNTHESIS AND CHARACTERIZATION OF CoFe2O4/Ni0.5Zn0.5Fe2O4 CORE/SHELL MAGNETIC NANOCOMPOSITE BY THE WET CHEMICAL ROUTE

Abstract

A cobalt ferrite/nickel-zinc ferrite core/shell nanocomposite was synthesized by a polymerized complex method using iron citrate, cobalt nitrate, nickel nitrate, zinc nitrate, citric acid, ethylene glycol, benzoic acid and sodium citrate as starting materials. The XRD, TEM and VSM techniques were employed to evaluate the phase composition, morphology and magnetic properties of the samples. The XRD results indicated the coexistence of characteristic reflections of CoFe 2 O 4 and Ni 0.5 Zn 0.5 Fe 2 O 4 spinel ferrites in the composite sample. The core/shell structure of the composite sample has been confirmed by TEM images. The size of obtained spherical core/shell nanoparticles was 20–40 nm in core diameter and about 10 nm in shell thickness. The VSM results showed that both the coercivity and the saturation magnetization of the resulting core/shell nanocomposite were decreased compared to those of the CoFe 2 O 4 core, due to the interaction at the interface of CoFe 2 O 4 and Ni 0.5 Zn 0.5 Fe 2 O 4.