Study of dielectric and magnetodielectric properties of Y-type Ba2Mg1.5Ni0.5Fe12O22 hexaferrite

We have investigated dielectric and magnetodielectric (MD) properties of polycrystalline Y-type hexaferrite Ba2Mg1.5Ni0.5Fe12O22 (BMNF). Rietveld refinement of the X-ray diffraction pattern and hexagonal plate-like Field Emission Scanning Electron Microscope (FESEM) micrograph confirms the phase purity with the rhombohedral crystal structure (R-3m space group). Both temperatures dependent dielectric permittivity (e׳) and dielectric loss (tan δ) show an anomaly around 150°C and 290°C. The comparable value of activation energy extracted from impedance spectroscopy above 290°C between σg and σgb indicates that relaxation and conduction mechanism may be attributing to the same entities. Room temperature magnetodielectric (MD) measurement at 1MHz indicates the step like increase at ∼8 kOe in dielectric constant (e) with applied field but a reverse trend is observed for magneto-loss (ML) with step like feature preserving it nature.We have investigated dielectric and magnetodielectric (MD) properties of polycrystalline Y-type hexaferrite Ba2Mg1.5Ni0.5Fe12O22 (BMNF). Rietveld refinement of the X-ray diffraction pattern and hexagonal plate-like Field Emission Scanning Electron Microscope (FESEM) micrograph confirms the phase purity with the rhombohedral crystal structure (R-3m space group). Both temperatures dependent dielectric permittivity (e׳) and dielectric loss (tan δ) show an anomaly around 150°C and 290°C. The comparable value of activation energy extracted from impedance spectroscopy above 290°C between σg and σgb indicates that relaxation and conduction mechanism may be attributing to the same entities. Room temperature magnetodielectric (MD) measurement at 1MHz indicates the step like increase at ∼8 kOe in dielectric constant (e) with applied field but a reverse trend is observed for magneto-loss (ML) with step like feature preserving it nature.