Assembly of Fe_3O_4 nanoparticles on SiO_2 monodisperse spheres

摘要

The assembly of superparamagnetic Fe_3O_4 nanoparticles on submicroscopic SiO_2 spheres have been prepared by an in situ reaction using different molar ratios of Fe~(3+)Fe~(2+) (50-280 percent). It has been observed that morphology of the assembly and properties of these hybrid materials composed of SiO_2 as core and Fe_3O_4 nanoparticles as shell depend on the molar ratio of Fe~(3+)/Fe~(2+).