High electromagnetic wave absorbing performance of activated hollow carbon fibers decorated with CNTs and Ni nanoparticles

摘要

Activated hollow carbon fibers (ACHFs) decorated with carbon nanotubes (CNTs) and nickel nanoparticles (CNTs-Ni-ACHFs) were prepared. by thermal reduction and chemical vapor deposition technique. Microwave reflection loss, permittivity and permeability of CNTs-Ni-ACHFs composites as novel electromagnetic wave absorbents were studied in the frequency range of 2-18 GHz. It was demonstrated that CNTs-Ni-ACHFs absorbents possessed the best microwave absorbing performances whose minimum reflection loss was 43.457 dB at 13.10 GHz with a thickness of 2.0 mm, which is much better than those of Ni-ACHFs and ACHFs samples. The dielectric polarizations and magnetic loss derived from the effect of the porous structures, Ni nanoparticles, and defects in the CNTs-Ni-ACHFs composites are playing an important role for the excellent microwave absorbing performances. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.