Comparative Dielectric Analysis of Co-Zr Doped M-Type Barium Hexaferrites BaCo_xZr_xFe_(12-2x)O₁₉ Prepared by Different Wet Chemical Routes

Abstract

Samples of barium hexaferrites (BaCo_xZr_xFe_(12-2x)O₁₉) with varying molar concentration of Cobalt and Zirconium were synthesized successfully by three different wet chemical routes: Sol gel, Citrate and self-combustion. Dielectric constant, dielectric loss tangent and AC Conductivity measurements were carried out in the frequency range 20Hz–1MHz over Impedance analyzer. Dielectric constant and loss tangent variations are explained on the basis of Maxwell-Wagner interfacial polarization in accordance with Koops phenomenological theory. AC Conductivity varies in accordance to Jonscher law (σ_ac = σ_dc + Aωⁿ) and shows normal behavior shown by other ferrites. The observed behavior of these samples suggests that the materials are suitable for applications in microwave devices. Three wet chemical routes are compared and it can be concluded that samples synthesized by citrate method are showing higher dielectric constant, low loss and low conductivity, hence are better.

Keywords:

• Hexagonal ferrites
• dielectric constant
• loss tangent
• AC conductivity
• Maxwell-Wagner model