Structural and dielectric properties of Gd-Zn substituted Ca0.5Ba0.5Fe12O19 M-type hexa-ferrites synthesized via auto-combustion method

Herein we studied the effect of Gd-Zn substitution on structural and dielectric properties of Ca0.5Ba0.5-xGdxZnyFe12-yO19 (x = 0.00, 0.04, 0.08, 0.10; y = 0.00, 0.40, 0.80, 1.00) synthesized by sol-gel autocombustion method. The prepared compounds were examined via XRD, SEM along with dielectric and electrical properties. Peak patterns of XRD analysis revealed the pure phase formation of M-type hexagonal ferrite. As concentration of Gd-Zn increases the lattice parameter were also found to increase. The scanning electron microscopy investigations revealed that the size of grain lies in between 1.19 and 0.58 mu m and the size of grains are reduced on increasing the substitution of Gd-Zn concentration. It is clear that the value of resistivity increases from 6.47 x 10(9) Omega-cm to 2.40 x 10(10) Omega -cm with increasing Gd-Zn concentration. The alteration in AC conductivity as a frequency function might be explained on the ground of Maxwell-Wagner model and of Koop's Phenomenological theory. The inspected alteration in dielectric constant could be illustrated on the behalf of hopping conduction between Fe2+ and Fe3+ and space charge polarization. The dielectric loss dispersion inspection is because of Koop's phenomenological theory and Maxwell-Wagner interfacial sort polarization. (C) 2018 Elsevier B.V. All rights reserved.