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 μm 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 × 10 9 Ω -cm to 2.40 × 10 10 Ω –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.