Electromagnetic interference (EMI) is an unwanted electromagnetic signal that disrupts the standard functioning of electronic equipment and also affects human health. These disturbances originate from multiple sources, including electronic devices, power lines, and lightning. This work investigates the microwave absorption performances of magnetic nanocomposites. Exchange coupling interaction is utilized to improve the microwave absorption properties. In this study, hard/soft nanocomposites were prepared using the sol-gel auto combustion method. Exchange-coupled nanocomposites are made by combining the hard phase ( Ba 0.5 Sr 0.5 Fe 12 O 19 ) with the soft phase ( Co 0.6 Ni 0.4 Fe 2 O 4 ) in different weight percentages (x = 0, 1, 0.1, 0.2, 0.3 & 0.4). The synthesized composites were characterized and analysed using various characterization techniques. The thermal stability and phase formation temperature were evaluated using TGA analysis over a temperature range from 0 °C to 1200 °C. XRD confirms the structural formation of the nanocomposites, along with the coexistence of the BSFO and CNFO phases. FTIR spectroscopy was used to analyze the bending and stretching vibrations of the sample. FE-SEM studies revealed the morphology and EDAX mapping of the samples. VSM was used to investigate the magnetic behaviour of the synthesized nanocomposites. At x = 0.1 and 0.2, the composite achieves a high magnetic saturation of 60.6 and 66.1 emu/g compared to the pure phase. The SFD curve exhibits a single peak for all samples, indicating a robust exchange-coupled effect between the two magnetic phases. The vector network analyzer was used to determine the microwave absorption performance in the X-band range of frequency. The RL min of composites x = 0.3 attain −21.5 dB with an optimal thickness of 2.5 mm at 10.2 GHz. • Hard/soft ferrite nanocomposites synthesized by the sol-gel auto combustion method. • Exchange coupling effect enhances the magnetic properties. • The SFD curve indicates a robust exchange-coupled effect. • RL min of −21.5 dB was achieved at 10.2 GHz with an optimal thickness of 2.5 mm.
Hariharan et al. (Sun,) studied this question.