Dielectric characterization of BaxSr1−xFe12O19 (x=0.05−0.35) ceramics

BaxSr1−xFe12O19 (x=0.05, 0.15, 0.25, 0.35) ferrites were prepared by both the sol-gel and conventional solid state reaction techniques. The structural characteristics and dielectric properties of these ferrites were investigated and compared. BaxSr1−xFe12O19 ceramics obtained by the sol-gel method show homogeneous morphology and single crystalline phase while those prepared by solid state reaction route exhibit less homogeneous morphology, being accompanied by a secondary crystalline phase (BaFe2O4). The size of the grains varies in the range 200-300 nm for x=0.05-0.35 when the powders are prepared by sol-gel method and, 600-700 nm for the powders prepared by solid state reaction. For the same value of x, the BaxSr1-xFe12O19 ferrites obtained via sol-gel display higher permittivity and lower dielectric losses compared to those prepared by solid state reaction route.