Chemical modification of magnetite with polythiophene and characterization of formed core-shell nanocomposite

Abstract

ABSTRACTIn this research, modified magnetite nanoparticles with polythiophene possessing core-shell structure were prepared by two-step methods. At the first, a coprecipitating method was employed for the formation magnetite nanoparticles in an ammonia solution as precipitant system. Next, the thiophene monomers were adsorbed on the surface of Fe3O4 nanoparticles and were then embedded the Fe3O4 nanoparticles via oxidative polymerization using FeCl3 as oxidant and H2O2 as redox catalyst in the solvent of acetonitrile. The morphology and particle size were obtained by scanning electron microscopy and transmission electron microscopy analysis and revealed a core-shell structure in the nanocomposite. The chemical structure and presence of polythiophene around Fe3O4 nanoparticles was confirmed by Fourier transform infrared spectroscopy and energy-dispersive X-ray analysis, respectively. The crystalline nature was characterized from X-ray diffraction line profile fitting and crystallite size was 15.9 and 18.2 for pure magnetite and nanocomposite, respectively. Magnetic properties were identified by vibrating sample magnetometer and revealed superparamagnetic behavior of Fe3O4/PTh nanocomposite. The improvement of the nanocomposite thermal stability by Fe3O4 nanoparticles was indicated by thermal gravimetric analysis. The results confirmed that the polythiophene was coated around the surface of magnetite nanoparticles that the diameter of Fe3O4 core was approximately 15 nm and the thickness of polythiophene shell was approximately 3–5 nm.