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 (RL_min) 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.