Magnetic and electrical properties of polypyrrole-coated -Fe2O3 nanocomposite particles

In this paper, we report the synthesis of well defined nanocomposite particles of polypyrrole (PPy) coated -Fe2O3. The nanocomposites with different -Fe2O3 contents are generated by microemulsion polymerization of pyrrole by dispersing -Fe2O3 in the oil phase. The structural properties of the nanocomposite particles thus obtained are characterized by FT-IR, thermal analysis, x-ray diffraction and transmission electron microscopy, which shows the size of the -Fe2O3PPy nanocomposite particles is in the range of 1020 nm. The magnetic and electrical properties of these particles are measured by vibrating sample magnetometry, Mossbauer spectroscopy and the four-point probe method which indicate that the nanocomposite particles are superparamagnetic and electrically conducting. The conductivity of the composite is independent of -Fe2O3 content.