Chemical route synthesis of nanostructured BaFe12O19 for microwave absorption application

The synthesis of M-type barium hexaferrite (BaM) has been achieved through a chemical route employing barium nitrate and ferric nitrate as initial reactants while utilising citric acid as a fuel. X-ray diffraction confirms the polycrystalline nature of BaM nanoparticles (NPs) with a hexagonal structure in the P6₃/mmc space group. The bending and stretching vibrations of metal-oxygen bonds are studied by Fourier Transform Infrared Spectroscopy. Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy were used for the morphological and compositional analyses. BaM NPs are embedded in an epoxy matrix, chosen for its excellent thermal, chemical, and physical properties, to fabricate a absorber for assessing microwave absorption (MA) performance. This study provides detailed insights into the structural, morphological, and compositional properties of BaM NPs for enhanced MA performance in the X-band region. The permittivity, permeability, and reflection loss of BaM1-BaM3 samples were analysed, revealing superior MA performance in the BaM3 nanocomposite compared to BaM1 and BaM2. Increasing the BaM NP concentration in the epoxy matrix from 10% to 30% elevates ε″ and μ″ values, boosting dielectric and magnetic losses due to enhanced interfacial and dipolar relaxation. This high magneto-dielectric loss in the BaM3 nanocomposite significantly improves MA performance.