Magnetic properties of hydrophilic iron oxide/polyaniline nanocomposites synthesized by in situ chemical oxidative polymerization

This work describes the preparation and characterization of polyaniline (PANI)/hydrophilic iron oxide nanocomposites synthesized from monodispersed 13 nm iron oxide (Fe3O4) nanoparticles and aniline monomer in HCl solution by in situ chemical oxidative polymerization. Hydrophilic 13 nm spherical Fe3O4 nanoparticles fabricated using the thermal decomposition process were modified using 11-aminoundecanoic acid tetramethylammonium salt. The modified Fe3O4 nanoparticles that served as cores were dispersed in an aqueous solution with anionic surfactant dodecylbenzenesulfonic acid sodium salt to form spherical templates and the PANI/Fe3O4 nanocomposites were then synthesized via in situ chemical oxidative polymerization on the surface of spherical templates. Structural and morphological analysis using X-ray diffraction and high-resolution transmission electron microscopy showed that the fabricated PANI/Fe3O4 nanocomposites are core (Fe3O4)-shell (PANI) structures. The magnetic properties of PANI/Fe3O4 nanocomposites exhibit supermagnetism with saturation magnetization in the range of 0.23–0.91 emu/g, depending on the amount of 13 nm Fe3O4 nanoparticles.