In situ synthesis and electromagnetic wave absorbing properties of sandwich microstructured graphene/La-doped barium ferrite nanocomposite

The development of high reflection loss and broad frequency bandwidth for electromagnetic wave absorbing materials has been pursued for a long time. Constructing a rational microstructure of an absorber will have significant impact on reflection loss increase and frequency bandwidth broadening. Herein, we successfully prepare a sandwich microstructured graphene/BaFe₁₂O₁₉ nanocomposite by an in situ auto-combustion method. Compared to pure BaFe₁₂O₁₉, the sandwich microstructured graphene/BaFe₁₂O₁₉ showed better electromagnetic wave absorbing properties. Furthermore, the sandwich microstructured graphene/Ba_0.8La_0.2Fe₁₂O₁₉ nanocomposite was prepared with La-doped BaFe₁₂O₁₉ using the same method. The obtained graphene/Ba_0.8La_0.2Fe₁₂O₁₉ nanocomposite exhibited a saturation magnetization of 26.55 emu g^-1 at room temperature and exhibited excellent magnetic performance. The maximum reflection loss of the sandwich microstructured graphene/Ba_0.8La_0.2Fe₁₂O₁₉ nanocomposite with a thickness of 1 mm could reach up to -40.26 dB, and a frequency bandwidth value below -10 dB was observed up to 3.87 GHz within the frequency range of 2-18 GHz.