Structural, magnetic, and dielectric properties of Ti4+-M2+co- doped BaFe11Ti0.5M0.5O19 hexaferrites (M=Co2+, Ni2+, Zn2+)

Pure BaFe12O19 and Ti4+ - M2+ co-doped BaFe11Ti0.5M0.5O19 (M = Co2+, Ni2+, Zn2+) hexaferrites were synthesized by a co-precipitation method. X-ray diffraction (XRD) patterns confirmed the formation of single-phase M-type hexagonal structure with P63/mmc space group. The structural analysis indicated that Ti - Ni and Ti - Zn co-doped samples enhanced the values of lattice parameters (a, c) and cell volume (V) in comparison to Ti - Co sample. Scanning electron microscopy (SEM) was used to investigate the effects of co-doping on the microstructure, whereas the elemental composition of prepared samples was verified by the energy dispersive X-ray spectroscopy (EDX). Impedance spectroscopy measurements revealed a significant variation in the dielectric properties of Ti4+ - M2+ co-doped samples which can be associated with the values of grain and grain boundary resistance. The magnetic hysteresis loops exhibited a ferrimagnetic behavior at room temperature. However, Ti Ni and Ti - Zn co-doped samples showed considerably high values of magnetization along with reduced coercivity. These variations in the obtained results are elucidated based on the site preferences of co-doped ions, mobility of charge carriers, and microstructure. Here, our findings of high dielectric permittivity, diminished dielectric tangent loss, better conduction, moderate magnetization and reduced coercivity for the Ti - Ni codoped BaFe11Ti0.5Ni0.5O19 sample make this composition favorable for electromagnetic absorbing applications.