Rational design of hierarchical structure of carbon@polyaniline composite with enhanced microwave absorption properties

Reasonable combination of components and ingenious structure design are effective strategies to achieve superior microwave absorption (MA). In this work, polyaniline was grown in situ on hollow porous carbon microspheres prepared by polymerization and pyrolysis-etching processes. The synthesized hollow porous carbon@polyaniline (HPC@PANI) shows a specific hierarchical structure and possesses extraordinary MA properties . The optimal minimum reflection loss ( RL ) of HPC@PANI is as high as −64.31 dB at 13.80 GHz with a thin thickness of 1.86 mm, and the corresponding effective absorption bandwidth (EAB, RL  ≤ −10 dB) is as wide as 4.85 GHz (11.90 GHz–16.75 GHz). The mechanism of such superior MA properties is associated with well impedance matching, strong loss capabilities and well-defined structural characteristics. It is expected that the design of HPC@PANI with hierarchical structures in this work could provide ideas for the structural design of efficient MA materials .