Broadband microwave absorption of Fe3O4-BaTiO3 composites enhanced by interfacial polarization and impedance matching

Nanocomposites composed of magnetic and dielectric materials are suitable for high performance electromagnetic wave absorbers due to their great impedance matching. In this work, the microwave absorbing properties of Fe3O4-BaTiO3 composites were investigated over a frequency range of 1-18 GHz Fe3O4-BaTiO3 composites present significantly enhanced microwave absorption performance compared with BaTiO3. For the optimal Fe3O4(x)-BaTiO3(1-x) (x = 0.8) composite, the reflection loss (RL) could reach -47.4 dB at 12.26 GHz with a matching thickness of 2.2 mm, the bandwidth below -10 dB is 5.0 GHz, which is six times higher than BaTiO3. The broadened absorption bandwidth is resulted from better impedance matching. This results show that Fe3O4-BaTiO3 composites can be used as an excellent microwave absorption materials with strong absorption and broad bandwidth.