Synthesis, Dielectric and Magnetic Properties of Mn⁺²-Substituted Y-Type Hexagonal Ferrites: Prospects for Microwave Absorption Applications

In this work, Y-type hexagonal ferrites are prepared by the sol–gel auto-combustion technique, aiming to enhance saturation magnetization and reduce coercivity while also improving the dielectric properties for microwave absorption applications. Scanning electron microscopy and crystallographic x-ray diffraction (XRD) are used to analyze their morphology and structural parameters. The XRD results confirm the presence of single-phase hexaferrites with crystallite sizes ranging from 51.5 nm to 69.0 nm. Fourier transform infrared spectroscopy demonstrates that the bond stretching of Fe–O ions at octahedral sites aligns with XRD analysis findings. Due to their properties, the dielectric constant values exhibit a decreasing trend with Mn concentration, making the synthesized materials suitable for microwave absorption applications. Substituting Mn²⁺ ions systematically enhances the AC conductivity. The magnetic properties are examined by vibrating-sample magnetometry. The decreasing trend in coercivity values with increasing Mn²⁺ concentration in the Y-type hexaferrites suggests the use of this material in magnetic sensing devices, magnetic recording, and microwave absorption.