Synthesis and Microwave Absorption Properties of Fe3O4/CuS Composites

A two‐step hydrothermal method is used to produce Fe 3 O 4 /CuS composites with a distinct layered structure of CuS. The composition, magnetism, and absorbing properties of the different proportions of Fe 3 O 4 /CuS composites are characterized. The results show that Fe 3 O 4 absorbs electromagnetic waves through orientation polarization and magnetically related natural resonance and that high conductivity enhances CuS microwave absorption. Compared with single‐phase Fe 3 O 4 and CuS, Fe 3 O 4 /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 Fe 3 O 4 and CuS. Based on these results, Fe 3 O 4 /CuS composites can be absorbers with a far wider microwave‐effective absorption bandwidth.