Ba ²⁺ ‐Substituted Strontium Hexaferrites (Sr _1−x Ba _x Fe ₁₂ O ₁₉ ): Composition‐Driven Optimization of Magnetic, Dielectric, and Optical Properties for Multifunctional Applications

ABSTRACT In the present work, Sr 1 − x Ba x Fe 1 2 O 1 ₉ nanoparticles (with x = 0.01, 0.02, 0.03, 0.04, and 0.05) were successfully prepared by the sol–gel method. The prepared samples were characterized using X‐ray diffraction, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) for investigation of structural, morphological, and functional groups. XRD analysis confirmed that the synthesized particles are nanosized with crystallite sizes ranging from 10–22 nm, as calculated using Scherrer's formula. The SEM images show uniform hexagonal‐shaped particles with slight agglomeration, which indicates good crystallinity together with a fairly homogeneous distribution of the nanoparticles. Ba 2 + ions inclusion significantly enhanced the magnetic behavior of the material, the saturation magnetization from 52.45 to 68.63 emu/g. This enhancement can be attributed to the larger ionic radius of Ba 2 + ions, which influences the crystal lattice. The AC conductivity shows a non‐linear relationship with the concentration of Ba 2 + ions. It reaches its highest value at x = 0.02, suggesting that this is the best level of doping for improving charge transport. UV–DRS, along with Tauc plot analysis, revealed a band gap in the range of 1.60 to 1.25 eV, confirming the semiconducting nature of the material. Finally, the observations indicate that Ba 2 + ‐doped strontium hexaferrite nanoparticles possess enhanced structural, electrical, optical, and magnetic properties.