Synthesis and characterization of poly(3-octylthiophene)/γ-Fe2O3 nanocomposite-A promising combination of superparamagnetic-thermoelectric-conducting properties

We report on the synthesis of poly(3-octylthiophene)/gamma-Fe2O3 nanocomposite by realizing the transfer of maghemite nanoparticles from aqueous solution to organic media. Monomer was polymerized in non-aqueous chloroform in the presence of the dispersed iron-oxide particles. The iron-oxide content of the composite was determined by atom absorption spectroscopy (ICP-AAS) and energy dispersive X-ray microanalysis technique (EDX). The molecular structure was characterized by UV-vis spectroscopy and photoacoustic Fourier transform infrared spectroscopy (PAS-FTIR). X-Fay diffraction (XRD) was used to characterize the supramolecular structure. Morphology change could be followed by scanning electron microscopy (SEM) which shows that the presence of maghemite particles during the synthesis results in a more compact structure consisting of spherical particles. The effective chain-length did not alter in comparison with the net polymer, moreover the structural change can be well correlated with the conductivity and capacity increase, determined from AC impedance spectroscopy measurements. The successful synthesis of the new composite possessing conducting, superparamagnetic and thermoelectric properties, can lead to possible applications. (C) 2008 Elsevier B.V. All rights reserved.