Preparation of Fe 3O 4/SiO 2 core/shell nanoparticles with ultrathin silica layer

Abstract

We successfully synthesized Fe 3O 4/SiO 2 nanoparticles with ultrathin silica layer of 1.0±0.5 nm that was fine controlled by changing concentration of Fe 3O 4. Among various reaction conditions for silica coating, increasing concentration of Fe 3O 4 was more effective approach to decrease silica thickness compared to water-to-surfactant ratio control. Moreover, we found that concentration of the 1-octanol is also important factor to produce the homogeneous Fe 3O 4/SiO 2 nanoparticles. The present approach could be available to apply on preparation of other core/shell nanoparticles with ultrathin silica layer.