Preparation and excellent electromagnetic absorption properties of dendritic structured Fe3O4@PANI composites

ABSTRACT Fe3O4, as a typical absorber, its electromagnetic wave (EMW) absorption properties are far from meeting the requirements of practical application due to its poor impedance matching. In this study, three kinds of novel heterogeneous structured composites, dendritic Fe3O4@(HCl doped PANI), Fe3O4@(p-TSA doped PANI) and Fe3O4@(dedoped PANI), were prepared via hydrothermal method combined with thermal reduction and in-situ polymerization, and their phase composition, microscopic morphologies, static magnetic properties, EMW absorption performance and absorption mechanisms were investigated. The results showed that the introduction of different medium doped and dedoped PANI greatly enhanced the EMW absorption performance of Fe3O4. The outstanding advantages of Fe3O4@(HCl doped PANI) were that the widest effective absorption bandwidth (EAB) up to 6.08 GHz in a relatively thin thickness of 2.1 mm. And the Fe3O4@ (dedoped PANI) composite achieved strong absorption ability (-53.08 dB@3.04 GHz) at low frequency in a relatively thin thickness (4.9 mm). The remarkable improvement of EMW absorption performance of dendritic Fe3O4@PANI composites could be attributed to the introduction of dissipation mechanisms, the optimization of impedance matching characteristics and the formation of appropriate conductive network microstructure. The dendritic Fe3O4@PANI composites are promising EMW absorption materials and have great practical application value.