In this paper,chemical co-precipitation method was employed to synthesize Fe3O4 nanoparticles which can be well dispersed in water by using citric acid as a surfactant.Afterwards,by using Fe3O4 nanoparticles as seeds ...In this paper,chemical co-precipitation method was employed to synthesize Fe3O4 nanoparticles which can be well dispersed in water by using citric acid as a surfactant.Afterwards,by using Fe3O4 nanoparticles as seeds in a Triton X-100/hexanol/cyclohexane/water reverse microemulsion system,the core-shell structural Fe3O4@SiO2 nanocomposite particles were prepared via hydrolysis and condensation of tetraethyl orthosilicate(TEOS) under the catalysis of alkali.The effects of different stirring methods and the concentration of TEOS on the morphology of Fe3O4@SiO2 nanoparticles were investigated.The results show that the mechanical stirring can effectively control the morphology of composite nanoparticles to form a good dispersion and spherical morphology of core-shell nanoparticles.With the increase of TEOS concentration,the thickness of the SiO2 shell increases,and the morphology of the composite particles becomes more uniform.展开更多
Nanoparticles of polystyrene/α Fe 2O 3 composites were prepared by method of insertion in sodium dodecylbenzene sulfonate(SDBS) micellar system. The orange α Fe 2O 3 particles of about 6 nm were first prepared from ...Nanoparticles of polystyrene/α Fe 2O 3 composites were prepared by method of insertion in sodium dodecylbenzene sulfonate(SDBS) micellar system. The orange α Fe 2O 3 particles of about 6 nm were first prepared from 0 25 mol/L FeCl 2 and (NH 3) 2CO 3 in 0.1% surfactant solution at pH=4, 105 ℃ for 10 h. The title nanoparticles were prepared then in conditions of SDBS∶ styrene∶H 2O(mass fraction)=0 1∶1∶9, 85 ℃, 8 h, using ammonium persulfate(APS) as an initiator. The composite nanoparticles sized in 20～50 nm and showed magnetic property.展开更多
文摘In this paper,chemical co-precipitation method was employed to synthesize Fe3O4 nanoparticles which can be well dispersed in water by using citric acid as a surfactant.Afterwards,by using Fe3O4 nanoparticles as seeds in a Triton X-100/hexanol/cyclohexane/water reverse microemulsion system,the core-shell structural Fe3O4@SiO2 nanocomposite particles were prepared via hydrolysis and condensation of tetraethyl orthosilicate(TEOS) under the catalysis of alkali.The effects of different stirring methods and the concentration of TEOS on the morphology of Fe3O4@SiO2 nanoparticles were investigated.The results show that the mechanical stirring can effectively control the morphology of composite nanoparticles to form a good dispersion and spherical morphology of core-shell nanoparticles.With the increase of TEOS concentration,the thickness of the SiO2 shell increases,and the morphology of the composite particles becomes more uniform.
文摘Nanoparticles of polystyrene/α Fe 2O 3 composites were prepared by method of insertion in sodium dodecylbenzene sulfonate(SDBS) micellar system. The orange α Fe 2O 3 particles of about 6 nm were first prepared from 0 25 mol/L FeCl 2 and (NH 3) 2CO 3 in 0.1% surfactant solution at pH=4, 105 ℃ for 10 h. The title nanoparticles were prepared then in conditions of SDBS∶ styrene∶H 2O(mass fraction)=0 1∶1∶9, 85 ℃, 8 h, using ammonium persulfate(APS) as an initiator. The composite nanoparticles sized in 20～50 nm and showed magnetic property.
