Preparation and electromagnetic wave absorption hard- soft ferrite/polypyrrole core-shell nanocompositesAuthor(s): Seyed Hossein Hosseini, Ahmed Asadnia, Maryam Moloudi
The nanocomposite of hard (BaFe12O19)/soft ferrite was prepared, and then the polypyrrole (PPy)-BaFe12O19/ Fe3O4 multi coreÂshell was produced by in situ polymerization method. X-ray diffraction, transmission electron microscope, scanning electron Microscopy and fourier transform infrared spectroscopy analysis indicated that Fe3O4 coated on the BaFe12O19 ferrite were homogenously enwrapped by PPy coating. The magnetic properties and electrical conductivity of the nanocomposite were characterized by vibrating sample magnetometer and four wire technique, respectively. As prepared conducting ferromagnetic polymer nanocomposites have electrical conductivity of the order of 5 S/cm and saturation magnetization (Ms) value of 3 emu/g. Microwave absorbing properties of the nanocomposite were investigated by using vector network analyzers in the frequency range of 8Â12GHz. The values of the minimum reflection loss were -23 dB at 10 and -28 dB at 11.5 GHz for Fe3O4 coated on the BaFe12O19/ Fe3O4/PPy core/ shell nanocomposite with a thickness of 1.5 mm.