Synthesis of hierarchical CuS/RGO/PANI/Fe3O4 quaternary composite and enhanced microwave absorption performance

Highlights: • A novel hierarchical composite of CuS/RGO/PANI/Fe₃O₄ was designed successfully. • The maximum R_L can reach −60.2 dB at 10.2 GHz. • The absorption bandwidth below −10 dB is 7.4 GHz with a thickness of 2.5 mm. • The mechanisms of enhanced microwave absorption properties are discussed. Quaternary composite of CuS/RGO/PANI/Fe₃O₄ was designed, and the effect of special microstructure on electromagnetic wave absorption performances was studied in detail. The structures, morphologies and chemical compositions of the as-prepared products were characterized by XRD, FESEM, TEM, FTIR and XPS. The measured electromagnetic wave absorption performances suggest that CuS/RGO/PANI/Fe₃O₄ possesses superior microwave absorption capacity, compared with CuS/RGO, CuS/RGO/PANI. The strongest reflection loss can achieve −60.2 dB at 10.2 GHz and absorbing bandwidth below −10 dB is 7.4 GHz (ranging from 7.5 to 14.9 GHz) for a coating of 2.5 mm. As an absorber, the enhanced microwave absorption performances of quaternary nanocomposite result from the synergistic effect, good impedance matching, and special hierarchical nanostructure. Above results demonstrate that the hybrid nanocomposite with strong absorption and wide frequency has a promising future in lessening EM wave interference.