Synthesis, characterization and excellent electromagnetic wave absorption properties of graphene@CoFe2O4@polyaniline nanocomposites

• The novel three-component nanocomposites of GN@CoFe2O4@PANI were synthesized.
• The nanocomposites had a ferromagnetic behavior.
• The maximum reflection loss of GN@CoFe2O4@PANI is −47.7 dB at 14.9 GHz.
• The absorption bandwidths exceeding −10 dB and −20 dB are 5.7 GHz and 2.0 GHz.

The novel three-component nanocomposites of graphene@CoFe2O4@polyaniline were firstly prepared by a simple hydrothermal process and an in situ polymerization. TEM and FESEM images showed that the incorporation of polyaniline could reduce the agglomeration of CoFe2O4 nanoparticles and VSM result revealed that the three-component nanocomposites had a ferromagnetic behavior. The measured electromagnetic parameters showed that the nanocomposites exhibited excellent electromagnetic wave absorption properties and broad absorption bandwidths due to the better impedance matching. The maximum reflection loss of the nanocomposites was up to −47.7 dB at 14.9 GHz with a thickness of 1.6 mm and the absorption bandwidths with reflection loss lower than −10 dB and −20 dB were 5.7 GHz and 2.0 GHz, respectively. Furthermore, the three-component nanocomposites with excellent electromagnetic wave absorption properties and wide absorption bandwidth can be used as a new kind of candidate for lightweight electromagnetic wave absorption materials.