Conducting and magnetic behaviors of monodispersed iron oxide/polypyrrole nanocomposites synthesized by in situ chemical oxidative polymerization

Abstract

Abstract This study describes the preparation of nanocomposites fabricated from monodispersed iron oxide (Fe 3 O 4 ) and polypyrrole (PPy) by in situ chemical oxidative polymerization. The monodispersed 4 nm Fe 3 O 4 nanoparticles which served as cores were synthesized using the thermal decomposition of a mixture of Iron (III) acetylacetonate and oleic acid in the presence of high boiling point solvents. The resulting nanoparticles were further dispersed in an aqueous solution with anionic surfactant sodium bis(2‐ethylhexyl) sulfosuccinate to form micelle/Fe 3 O 4 spherical templates that avoid the aggregation of Fe 3 O 4 nanoparticles during the further preparation of the nanocomposites. The Fe 3 O 4 /PPy nanocomposites were then synthesized via in situ chemical oxidative polymerization on the surface of the spherical templates. Both field‐emission scanning electron microscopy (FESEM) and high‐resolution transmission electron microscopy (HRTEM) images indicate that the resulting Fe 3 O 4 nanoparticles are close to spherical dots with a particle size of about 4 nm and a standard deviation of less than 5% (4 ± 0.2 nm). Structural and morphological analysis using FESEM and HRTEM showed that the fabricated Fe 3 O 4 /PPy nanocomposites are core (Fe 3 O 4 )‐shell (PPy) structures. Morphology of the nanocomposites shows a remarkable change from spherical to tube‐like structures as the content of monodispersed Fe 3 O 4 nanoparticles increases from 9% up to 24 wt %. The conductivities of these Fe 3 O 4 /PPy nanocomposites are about six times higher than those of PPy without Fe 3 O 4 . © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4647–4655, 2007