Hydrothermal synthesis of near-monodisperse iron oxide nanoparticles using an ammonia-treated Fe-oleate precursor

Abstract

This paper discusses the hydrothermal synthesis of monodisperse oleate-capped iron oxide nanoparticles from an ammonia-treated Fe-oleate precursor solution. Nanoparticle samples synthesized at different temperatures were characterized using a combination of X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, dynamic light scattering, vibrating sample magnetometry, and thermogravimetry-differential thermal analysis. This characterization revealed nanoparticles comprising inverse-spinel-type crystals covered by an oleate double-layer, with the saturation magnetization of the nanoparticles increasing with the temperature used for hydrothermal synthesis. Near-monodisperse nanoparticle distributions were obtained with hydrothermal reactions conducted at 150 °C.