Phase Stablization and Frequency Dependent Dielectric Response of La-doped Sr-hexaferrites

A series of Sr1-xLaxFe12O19 (x = 0, 0.1, 0.15 and 0.2) ferrites have been synthesized using a novel sol-gel based auto-combustion route. The phase stabilization of pure hexagonal SrFe12O19 was exhibited by X-ray diffraction. The diffraction data was utilized to index the intensity peaks, following the methodology described by Cullity. The structural parameters such as lattice constant, unit cell volume, crystallite size, X-ray density and porosity of the samples were also evaluated from the data. All these parameters were observed to be influenced by the increase in La contents at Sr-sites. Dielectric constant was found to decrease with the increase in frequency and doping of lanthanum in SrFe12O19, attributed to the relaxation process.