Synthesis and Microwave Absorption Properties of Fe₃O₄/CuS Composites

A two-step hydrothermal method is used to produce Fe₃O₄/CuS composites with a distinct layered structure of CuS. The composition, magnetism, and absorbing properties of the different proportions of Fe₃O₄/CuS composites are characterized. The results show that Fe₃O₄ absorbs electromagnetic waves through orientation polarization and magnetically related natural resonance and that high conductivity enhances CuS microwave absorption. Compared with single-phase Fe₃O₄ and CuS, Fe₃O₄/CuS composites exhibit superior microwave absorption performance with a considerably reduced matching thickness and increased effective absorption bandwidth in the 1–18 GHz range, which can be attributed to the interfacial coupling-induced polarization between heterostructure Fe₃O₄ and CuS. Based on these results, Fe₃O₄/CuS composites can be absorbers with a far wider microwave-effective absorption bandwidth.