Investigation on structural, hysteresis, Mössbauer properties and electrical parameters of lightly Erbium substituted X-type Ba2Co2ErxFe28-xO46 hexaferrites

A series of Erbium substituted X-type Ba<inf>2</inf>Co<inf>2</inf>Er<inf>x</inf>Fe<inf>28-x</inf>O<inf>46</inf> (x = 0.00, 0.04, 0.08, 0.12, 0.16, and 0.20) hexaferrites were prepared by the method of heat treatment. The obtained precursors were heated at 1350 °C for 6 h. XRD investigation reveals that x = 0.0 sample possesses X, W-type, and α-Fe<inf>2</inf>O<inf>3</inf> phases, while Er- substituted samples show presence of X and W phases. The room temperature Mössabuer spectra have been fitted with five sextets. A variation in saturation magnetization (M<inf>S</inf>) is explained and supported by the Mössbauer spectroscopy. The maximum values of M<inf>S</inf> (52.29 Am²/kg) and anisotropy field-Ha (1370 kA/m) are found for x = 0.12 composition. Similarly, the maximum relative area (~69%) for spin up sites (k+a+b) is also found for x = 0.12 composition. Low frequency (20 Hz–2 MHz) dielectric response of all samples show normal behavior of ferromagnetic materials. The dielectric measurements reveal that the conduction in low frequency is due to grain boundary contributions and at the higher frequency it is due to grain contributions. AC conductivity is found to increase with frequency in all prepared hexaferrites. The substituted compositions can have potential applications in filter application due to soft ferrite behavior and low dielectric loss tangent.