Hierarchical flower-like Fe3O4/MoS2 composites for selective broadband electromagnetic wave absorption performance

The brilliant electromagnetic wave (EMW) absorbers are urgent with the extensive attention of electromagnetic pollution. Herein, the binary Fe3O4/MoS2 composites are successfully synthesized via a facile hydrothermal method, where the different morphologies of 3D MoS2 nanoflowers decorated with the monodispersed Fe3O4 particles by tailoring the molar ratio of Fe3O4 to MoS2. Moreover, we find that the dielectric/magnetic loss and good impedance matching have dramatically contributed to the enhanced EMW absorption ability for binary Fe3O4/MoS2 composites compared to pristine Fe3O4 nanoparticles. Meanwhile, the effective absorption bandwidth (EAB, RL < -10 dB, > 90% absorption) of 6.1 GHz at thin thickness of 2.0 mm could be obtained while it exhibits the strongest minimum reflection loss (RLmin) of -64.0 dB with ultra-thin thickness of 1.7 mm. Noticeably, even for the low frequency of C (4-8 GHz) and X (8-12 GHz) bands, the 100% frequency occupy ratio can be realized while the RL intensity is still not severely deteriorated, which is superior than most of MoS2-based absorbers that have been reported so far. Hence, it can be expected that the Fe3O4/MoS2 composites in this work featured with strong absorption intensity, selectable wide bandwidth (especially for 100% coverage both for C and X bands) as well as ultra-thin thickness (EAB of 6.1 GHz at 2.0 mm) will ensure it an attractive EMW absorber.