Synthesis of hollow poly(aniline-co-pyrrole)–Fe3O4 composite nanospheres and their microwave absorption behavior

Abstract Hollow poly(aniline- co -pyrrole)–Fe 3 O 4 (HPAP–Fe 3 O 4 ) nanospheres with significant electromagnetic properties were successfully prepared via the oxidative polymerization of a mixture of aniline and pyrrole in the presence of a magnetic fluid, using a non-ionic surfactant as a template. The products were characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetric analysis and X-ray photoelectron spectroscopy. The electromagnetic (EM) and microwave absorbing properties of the nanocomposites were also investigated. The HPAP–Fe 3 O 4 nanospheres exhibit superparamagnetic properties, and the conductivity increases with Fe 3 O 4 content. The reflection loss evaluation based on the absorbing wall theory at 2 mm thickness shows that the reflection loss is reinforced in the frequency range of 0.5–10 GHz by the presence of Fe 3 O 4 nanoparticles, and the frequency of minimum reflection loss shifts to a higher value with increasing Fe 3 O 4 content. HPAP–Fe 06 exhibits the best microwave absorbing property between 0.5 and 10 GHz.