Room Temperature Synthesis of Magnetite Particles by an Oil Membrane Layer-Assisted Reverse Co-Precipitation Approach

Abstract

Reverse co-precipitation (RCP) in ambient atmosphere is one of the strategies to produce magnetite nanoparticles in a rapid, simple, and cost-effective synthesis route without applying temperature surfactants or inert gases. However, RCP of ferrous/ferric blended salt in sodium hydroxide (NaOH) solution in an oxidizing medium produced of maghemite as a dominant phase rather than magnetite because of the oxidation of Fe2+ to Fe3+ happened. Based on this background, an oil membrane layer-assisted reverse co-precipitation approach has been examined to synthesis of magnetite in ambient atmosphere at room temperature. The result showed that although addition of benzene as an oil membrane layer was effective to prevent oxidation of magnetite to maghemite, but the magnetite particle size for the samples from the oil membrane layer-assisted reverse co-precipitation method was much larger than that from a reverse co-precipitation method without addition of oil membrane layer.