Influence of Nickel Substitution on Crystal Structure and Magnetic Properties of Strontium Ferrite Preparation Via sol- gel Auto- Combustion Route

Abstract

In this research, SrFe12−xNixO19 (x = 0 − 1) hexagonal ferrites were prepared by<br><br>sol-gel auto-combustion method. Effect of Ni substitution on structural, morphological<br><br>and magnetic properties of nanoparticles was investigated by X-ray diffraction (XRD),<br><br>Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM) and vi-<br><br>brating sample magnetometer (VSM), respectively. The XRD results confirmed that all<br><br>samples with x ≤ 0.5 have single phase M-type strontium ferrite structure, whereas for<br><br>the SrFe12−xNixO19 samples with x &gt; 0.5, the spinel NiFe2O4 phase has also appeared.<br><br>The lattice parameters and crystallite sizes of the powders were concluded from the<br><br>XRD data and Williamson–Hall method. Magnetic analyses showed that the coercivity<br><br>of powders decreased from 5672 Oe to 639 Oe while the saturation magnetization in-<br><br>creased from 74 emu/g to 81 emu/g with nickel substitution. The results of this study<br><br>suggest that the strontium hexaferrites doped with Ni are suitable for applications in<br><br>high density magnetic recording media as well as microwave devices because of their<br><br>promising magnetic properties.