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Poly(ethylene glycol)(PEG) assisted hydrothermal route has been used to study the influence of the hydrolyzing agent on the properties of PEG-iron oxide(Fe_3O_4) nanocomposites.Iron oxide nanoparticles(NPs),as confirmed by X-ray diffraction analysis,have been synthesized by a hydrothermal method in which Na OH and NH_3 were used as hydrolyzing agents.Formation of PEG-Fe_3O_4 nanocomposite was confirmed by Fourier transform infrared spectroscopy(FTIR).Samples exhibit different crystallite sizes,which estimated based on line profile fitting as 10 nm for NH_3 and 8 nm for Na OH hydrolyzed samples.The average particle sizes obtained from transmission electron microscopy was respectively 174±3 nm for Na OH and 165±4 nm for NH3 gas hydrolyzed samples.Magnetic characterization results reveal superparamagnetic characteristics despite a large particle size,which indicate the absence of coupling between the nanocrystals due to the presence of polymer in the nanocomposites.The conductivity curve demonstrates that σDC is strongly temperature dependent.
Poly (ethylene glycol) (PEG) assisted hydrothermal route has been used to study the influence of the hydrolyzing agent on the properties of PEG-iron oxide (Fe_3O_4) nanocomposites. Iron oxide nanoparticles (NPs), as confirmed by X-ray diffraction analysis , have been synthesized by a hydrothermal method in which NaOH and NH3 were used as hydrolyzing agents. Formation of PEG-Fe3O4 nanocomposite was confirmed by Fourier transform infrared spectroscopy (FTIR). Samples exhibit exhibit different crystallite sizes, which estimates based on line profile fitting as 10 nm for NH 3 and 8 nm for Na OH hydrolyzed samples. The average particle sizes obtained from transmission electron microscopy were respectively 174 ± 3 nm for Na OH and 165 ± 4 nm for NH 3 gas hydrolyzed samples. Magnetic characterization results reveal superparamagnetic line a large particle size, which indicate the absence of coupling between the nanocrystals due to the presence of polymer in the nanocomposites. the conductivity curv e demonstrates that σDC is strongly temperature dependent.