Formation of magnetic microstructure of the nanosized NiFe2O4 synthesized via solid-state reaction

T Zák,D Zivkovic,N Talijan,V Cosovic,B David,A Cosovic

doi:10.2298/sos1201103z

Abstract

Magnetic NiFe2O4 structure formation was studied through structural, compositional and magnetic characterization of obtained reaction products of a simple, high yielding and low-cost solid-state reaction. Initial annealing of the starting oxides mixture at 700?C did not allow us to observe formation of the desired magnetic phase. In contrast, subsequent thermomagnetic measurements up to 800?C indicated the considerable increase of the magnetic moment, which can be reasonably assigned to the changes in phase composition and formation of magnetic NiFe2O4 structure during the heating cycle of measurements. Nanosized NiFe2O4 phase formation has been confirmed by the following XRD and MS phase analyses and its nanocrystalline structure by XRD and SEM/TEM techniques. The obtained hysteresis loop taken after TM measurements suggest the increased volume of magnetically active material and thus additionally support the previous findings.

Highlights

The soft or low coercivity ferrites are the most widely used group of magnetic materials utilized by electrical, electronic, information and home appliance industry, representing very important basic functional materials
Subsequent thermomagnetic measurements up to 800oC indicated the considerable increase of the magnetic moment, which can be reasonably assigned to the changes in phase composition and formation of magnetic NiFe2O4 structure during the heating cycle of measurements
The considerable increase of the magnetic moment with a decrease of temperature was observed on the obtained thermomagetic curve

Summary

Introduction

The soft or low coercivity ferrites are the most widely used group of magnetic materials utilized by electrical, electronic, information and home appliance industry, representing very important basic functional materials They are non-conductive ceramic materials based on iron oxides as well as nickel, zinc, and/or manganese compounds [1]. Their high electrical resistivity facilitates fairly low energy losses at high frequencies They are extensively used in such applications where reduction of the different losses accompanying high-frequencies is more important than the static magnetic properties [2]. The usual drawback of the conventional solidstate reactions for the preparation of Ni-ferrites is that at high temperatures, formation of a polycrystalline ferrite compound with a large crystallite size is favored This leads to loss of their peculiar structural and magnetic properties [7]. Given that the magnetic properties of NiFe2O4 ferrite magnetic materials are directly related to their structure and phase composition, formation of magnetic microstructure of the nanosized nickel ferrite synthesized via solid-state reaction was analyzed and discussed through structural, compositional and magnetic characterization of obtained reaction products

Experimental

Results and Discussion

Conclusions