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

Abstract

In this paper, we report the synthesis of well defined nanocomposite particles of polypyrrole (PPy) coated γ-Fe2O3. The nanocomposites with different γ-Fe2O3 contents are generated by microemulsion polymerization of pyrrole by dispersing γ-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 γ-Fe2O3-PPy nanocomposite particles is in the range of 10-20 nm. The magnetic and electrical properties of these particles are measured by vibrating sample magnetometry. Mössbauer 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 γ-Fe2O3 content.