Magnetic property modulation in barium hexaferrites through Al-Ga substitution using sol–gel combustion synthesis

Detailed investigations have been performed on the magnetic properties of BaAl[Formula: see text]Ga[Formula: see text]Fe[Formula: see text][Formula: see text]O[Formula: see text] (0.1 [Formula: see text][Formula: see text] [Formula: see text] 1.0) polycrystals which were synthesized using a citrate sol–gel method. The results indicate that [Formula: see text], [Formula: see text], and [Formula: see text] decrease consistently as the doping content increases from 0.1 to 1, and the particle sizes are about 100–550 nm. The XRD data indicate that the successful substitution of Al–Ga at Fe sites takes place, leading to the generation of pure barium hexaferrite in all samples. The EDS pattern confirms the presence of Ba, Fe, O, Al, and Ga. Both the maximum applied-field magnetization ([Formula: see text]) and the magnetization at zero field (Mr) decrease consistently with the doping level ([Formula: see text][Formula: see text]0.1–1). The coercive force (Hc) increases congruously with increasing doping content. Both the maximum [Formula: see text] and Mr were obtained at [Formula: see text][Formula: see text]0.1 with values of 55.24 and 33.33 Am 2 /kg, respectively. The maximum coercive force Hc obtained at [Formula: see text] [Formula: see text] 1 is 523 kA/m. This study demonstrates that the attainment of application-specific magnetic properties tailored to practical requirements can be realized by the precise regulation of doping concentrations.