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

Hollow poly(aniline-co-pyrrole)-Fe3O4 (HPAP-Fe3O4) 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 Xray photoelectron spectroscopy. The electromagnetic (EM) and microwave absorbing properties of the nanocomposites were also investigated. The HPAP-Fe3O4 nanospheres exhibit superparamagnetic properties, and the conductivity increases with Fe3O4 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 Fe3O4 nanoparticles, and the frequency of minimum reflection loss shifts to a higher value with increasing Fe3O4 content. HPAP-Fe-06 exhibits the best microwave absorbing property between 0.5 and 10 GHz. (C) 2011 Elsevier B.V. All rights reserved.