Preparation of Fe (core)/SiO2 (shell) composite particles with improved oxidation-resistance

The preparation of silica coated iron particles with improved oxidation-resistance was described in the paper. XRD, TEM and XPS were used to characterize the product, which indicated that a thin film of silica was coated on the surface of Fe particles through a silica–oxide–iron bond. The content of silica to iron in the sample was quantitatively determined by ICP. Magnetic measurements results of the particles almost kept constant before and after coating process. DTA and TG results showed that the coating shell of silica could effectively protect the Fe cores from oxidation.