Effect of lanthanum doping on barium hexaferrites: Structural and magnetic properties via sol-gel synthesis using galactose

The structural and magnetic properties of barium hexaferrite was investigated by the effect of Lanthanum (La) doping by sol-gel method with varying concentrations (x = 0.00, 0.01, 0.02, 0.03, 0.04, 0.05), in which the resulting BHFs calcined at 800 °C for 2 h to achieve the new phase formation. The galactose green precursor in sol-gel route is an ecofriendly technique, which prevents agglomeration and well controlled dispersion of BHF NPs. Very importantly, this approach reduces the calcination temperature. Also, controlled morphology, particle size and also this method is low cost suitable for large scale production. The XRD analysis confirmed the successful formation of M-type hexaferrite phase, with crystalline size ranged 16–24.8 nm with an average size of 18.36 nm. Fourier-transform infrared (FTIR) spectroscopy identified the characteristic absorption bands between 430 and 590 cm⁻¹, corresponding to metal-oxide stretching and bending vibrations further validating the phase formation. The magnetic measurements at room temperature revealed a crucial trend: the coercivity (Hc) decreased gradually with increasing La concentration, while saturation magnetization (Ms) and remanent magnetization (Mr) showed only slight variations which indicates a transition towards a soft magnetic nature. To get insight into BHF nanoparticles the morphology and elemental distribution, field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDAX) analysis was performed. The ability to modify the magnetic properties through controlled La doped BHF highlights its potential for next generation magnetic and electronic technologies.