Abstract:
Spinel structures are lately being explored widely because of their crucial applications in
electromagnetic absorbing materials, high frequency devices, memory devices,
photocatalysts and catalysts. The exponentially remarkable electrical and magnetic
properties of ferrites have always been of prime interest which leads to their extensive
commercial use. In present study barium monoferrite with formula Ba1-xCoxFe2O4 where
x= 0.00 ,0.20 ,0.35 ,0.50 ,0.75, 1.00 has been prepared through sol gel auto-combustion
method. Stoichiometric ratios of citric acid, barium, cobalt and iron nitrates along with
ammonia solution for maintaining solution’s pH were used for the preparation of samples.
Samples were calcinated at 800 °C for 4 hours. Sample characterization was made using
X-Ray Diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR).
Electrical and magnetic behaviors were analyzed through Vibrating sample magnetometer
and RF impedance analyzer. Formation of Ba1-xCoxFe2O4 was confirmed using XRD.
Crystallite sizes were calculated through Debye Scherer formula which lie in the range
(26-40)±5 nm. Octahedral and tetrahedral band positions were confirmed using FTIR data.
Room temperature frequency dependence of dielectric properties were observed to be
enhanced till certain concentrations, then a decreasing trend was observed. Dielectric
constant was increased from 5.7 to 16.7 for x=0.35 at 1MHz. The magnetic properties of
prepared samples showed an increase in saturation magnetization from 2.69 emu/g at
x=0.00 to 84.8 emu/g at x=1.00. A decrease in magnetic coercivity is observed with
increase in concentration. The high and quite comparable values of dielectric constant
make this material suitable for use as a microwave absorbing paint as well as a promising
Electromagnetic Interference (EMI) shielding material.
