▎ 摘　　要

M-type barium hexaferrite with composition BaCo0.2Ti0.2Fe11.6 O-19 was synthesized by sol-gel method and nanocomposites of Reduce Graphene Oxide/BaCo0.2Ti0.2Fe11.6O19 were also synthesized by hydrothermal method. The electromagnetic (EM) characteristics were studied in the frequency range of 2-18 GHz. The x-ray diffraction analysis confirms the formation of required nanocomposites and Scanning Electron Microscopy (SEM) analysis depicts the spherical morphology of BaCo0.2Ti0.2Fe11.6O19 (BCTF) nanoparticles, which are embedded in Reduce Graphene Oxide (RGO) sheets. The Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy confirm the purity of required phases. The Raman Spectra shows that ID/IG ratio increases from 0.967 to 1.379 for RGO/BCTF nanocomposites and produce defects in the sample. The magnetic properties were measured by vibrating sample magnetometer (VSM) in the magnetic field ranged from +/- 12,000 Oe. The RGO/ BCTF transforms in to soft ferrite by the doping of Co2+ and Ti4+ cation in M-type hexagonal ferrite. The complex permittivity and permeability were measured by vector network analyzer in the frequency range of 2-18 GHz. The minimum Reflections Loss (RL) reached-18.24 dB for RGO/BCTF at frequency of 6.8 GHz with a thickness of 2 mm and also broadens the effective absorption bandwidth from 3.77 to 4.5 GHz. The effect of coating thickness (1-2 mm) transforms the absorption peaks towards higher frequency with decrease in matching thickness.