Abstract: Firstly, a mixture solution of Fe₃O₄ nanoparticles and graphene oxide was prepared by solutionblending method. Then, 
Fe₃O₄/rGO composite film was prepared by stepbystep thermal reduction method from room temperature up to 160 ℃. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy were used to characterize the structure and morphology of the films with different mass fractions of Fe₃O₄. We used vector network analyzer to test electromagnetic parameters of the composite film. The results show that when the mass fraction of Fe₃O₄ is 40%, the absorbing wave performance of the composite film is 17.30 dB at frequency of 1072 GHz with a matching thickness of 2.0 mm, and the effective absorption bandwidth less than -10 dB is 3.28 GHz.

Key words: composite material； graphene； electromagnetic wave； electromagnetic shielding, absorbing wave