Abstract
A new process to prepare single-phase nano-sized ferrites, Ni
0.8−
x
Cu
0.2Zn
x
Fe
2O
4 with
x
=
0.1–0.7, was developed using egg-white precursors. TG measurement showed that, the precursors must be calcined at 550
°C. XRD patterns indicated the formation of single-phase cubic ferrites with particle size in the range 28.7–48.4
nm. TEM image gave particle size agrees well with that estimated using XRD. FT-IR spectroscopy showed the characteristic ferrite bands. Hysteresis loops measurements exhibited an increase in the saturation magnetization value (
M
s) up to zinc content of 0.2 followed by unexpected decrease, which suggests the preference of Zn
2+ ions to occupy octahedral sites. The decrease in the coercivity (
H
c) with increasing zinc content is attributed to the lower magneto-crystalline anisotropy of Zn
2+ ions compared to Ni
2+ ions. Temperature dependence of the molar magnetic susceptibility (
χ
M) suggested a ferrimagnetic behavior of the investigated samples and showed a decrease in the value of the Curie temperature (
T
C) with increasing zinc.