Facile preparation of CNTs microspheres as improved carbon absorbers for high-efficiency electromagnetic wave absorption

Carbon nanotubes microspheres (CNTsM) with porous skeleton and net structure were successfully prepared by a facile method of ultrasonic atomization combined with heat treatment. Dielectric characteristics and electromagnetic wave (EMW) absorption properties within the frequency range of 2-18 GHz of CNTsM were studied. Owing to increased multiple reflection/scattering, enhanced interfacial polarization and optimized impedance matching, an excellent EMW absorption performance is therefore obtained for CNTsM. The maximum reflection loss (RL) reaches-35 dB at the thickness of 4.6 mm, and a wide effective absorption bandwidth (EAB, RL <-10dB) of 4.4 GHz is achieved with a thickness of 1.5 mm. CNTsM can be regarded as a brand-new competitive candidate for EMW absorption materials.

Automated summary

In this study, carbon nanotubes microspheres (CNTsM) with porous skeleton and net structure were successfully prepared using a simple method of ultrasonic atomization combined with heat treatment. The dielectric characteristics and electromagnetic wave (EMW) absorption properties of CNTsM within the frequency range of 2-18 GHz were investigated, showing excellent EMW absorption performance due to multiple reflection/scattering, enhanced interfacial polarization, and optimized impedance matching. CNTsM can be considered a new competitive candidate for EMW absorption materials, with a maximum reflection loss of -35 dB and a wide effective absorption bandwidth of 4.4 GHz.