Abstract:
Ni0.6Zn0.4-xMgxFe2O4 (x = 0.0, 0.1, 0.15, and 0.2) nanoferrites were successfully synthesized
by the sol-gel combustion method. The structural, optical and magnetic properties of these
materials were investigated using x-ray powder diffraction (XRD), field emission scanning
electron microscopy (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy,
ultraviolent visible (UV-Vis) spectroscopy, and vibration sample magnetometer
(VSM). From the XRD analysis, the lattice parameters and the unit cell volumes of the
synthesized samples decreased with an increase in Mg content up to x = 0.15, after which it
was increased with a further addition of Mg content (x = 0.2). The crystallite sizes were
found between 47.5 and 71.5 nm, indicating that all the synthesized materials possessed a
nanocrystalline structure. The FE-SEM micrographs confirmed that all samples have nearly
spherical shaped grains with some agglomeration. From FT-IR measurements, the higher
frequency bands υ1 were appeared between 583.0 and 596.2 cm
-1
, and the lower frequency
bands υ2 were also appeared between 429.7 and 476.7 cm
-1
. These bands revealed the
presence of the stretching vibration of the metal-oxygen ions at the tetrahedral and
octahedral sites. From the optical property study, it was identified that all the synthesized
samples were optically activated under ultraviolent light. The optical band gap energies
were found between 1.7 and 1.83 eV. The magnetic property study confirmed the soft
magnetization behavior of the synthesized samples at room temperature. The squareness
ratio values of all samples were found to be less than 0.5, indicating the formation of multi domain grains
