摘要
Nowadays,the novel oil water interface method has attracted a considerable attention owing to the advantages of mild reaction conditions,simple operation,low cost,and high efficiency.In this paper,uniform oil-soluble Fe_3O_4 nanoparticles(NPs) were synthesized by oil-water interface method from mixing iron tristearate of 0.067mol/L in cyclohexane with ferrous sulfate in water.The as-prepared products were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),vibrating sample magnetometer(VSM),Fourier transform infrared spectroscopy(FT-IR) and thermogravimetric analyzer(TGA).TEM images and XRD profiles showed that the size of the oil-soluble products ranged in 1.7-6.9 nm.VSM indicated that the Fe_3O_4 NPs were superparamagetic.FT-IR and TGA proved that oleic acid was combined to the surface of Fe_3O_4 NPs closely.TEM images and XRD profiles revealed that the most suitable reaction concentration of NH_3·H_2O,oleic acid/water in volume,reaction temperature and reaction time were 4.5 mol/L,50:1 000,80℃ and 6 h,respectively.The formation mechanism of the nearly monodispersed Fe_3O_4 NPs was that the preformed Fe_3O_4 nuclei were capped by oleic acid as early as the nucleation occurred in oil-water interface and subsequently entered into oil phase to stop growing.
Nowadays,the novel oil water interface method has attracted a considerable attention owing to the advantages of mild reaction conditions,simple operation,low cost,and high efficiency.In this paper,uniform oil-soluble Fe3O4 nanoparticles（NPs） were synthesized by oil-water interface method from mixing iron tristearate of 0.067mol/L in cyclohexane with ferrous sulfate in water.The as-prepared products were characterized by X-ray diffraction（XRD）,transmission electron microscopy（TEM）,vibrating sample magnetometer（VSM）,Fourier transform infrared spectroscopy（FT-IR） and thermogravimetric analyzer（TGA）.TEM images and XRD profiles showed that the size of the oil-soluble products ranged in 1.7-6.9 nm.VSM indicated that the Fe3O4 NPs were superparamagetic.FT-IR and TGA proved that oleic acid was combined to the surface of Fe3O4 NPs closely.TEM images and XRD profiles revealed that the most suitable reaction concentration of NH3·H2O,oleic acid/water in volume,reaction temperature and reaction time were 4.5 mol/L,50：1 000,80℃ and 6 h,respectively.The formation mechanism of the nearly monodispersed Fe3O4 NPs was that the preformed Fe3O4 nuclei were capped by oleic acid as early as the nucleation occurred in oil-water interface and subsequently entered into oil phase to stop growing.
基金
Nanometer Special Project of Shanghai,China(No.1052nm06400)
