Investigation of microwave-absorbing properties of aligned polyaniline/multi-walled carbon nanotubes nanocomposites

A aligned polyaniline/carbon nanotubes (a-PANI/CNTs) nanocomposite was synthesized by in situ polymerization. The structural and the microwave-absorbing properties of the a-PANI/CNTs nanocomposites were studied. Transmission electron microscopy, X-ray diffraction and Raman spectra were carried out to confirm the formation of a vertically grown PANI array on the surface of the CNTs. With a matching thickness of 1.5 mm, the a-PANI/CNTs had a maximum reflection loss of about −29.49 dB. Moreover, the bandwidth corresponding to reflection loss below −10 dB was about 4.42 GHz (13.58 GHz to 18.00 GHz), which is significantly better than those of CNTs, PANI and PANI/CNTs. We ascribed the enhanced microwave-absorbing properties to the unique ordered structure of aligned PANI.