Abstract
Magnetic nanoparticles draw great attention from the field of technology and science due to their extensively application as advanced functional materials on magnetic storage, MRI contrast agent, drug delivery, and catalysis. Iron oxide nanoparticles have many merits such as non-toxicity, chemistry stable, and low-cost; hence, we have to pay our effort on the investigation of these nanoparticles. Traditionally, iron oxide nanoparticles have been synthesized by aqueous solution method, which involved the reduction reaction of ferrous and ferric ions. However, in recent, more and more method have been developed for nanoparticles synthesis. These strategies for nanoparticles synthesis all involved the high temperature reaction that is easy to obtain monodisperse and high-quality nanoparticles. In this thesis, we applied a non-aqueous system to synthesis iron oxide nanoparticles. From many characterizations such as TEM, XRD, and XPS, we confirm these iron oxide nanoparticles to magnetite (Fe3O4) phase that is the most interesting iron oxide species due to its half-metal property. Besides, by tuning growth factors, the shape of nanocrystals can be changed from spherical to cubelike. Other surfactants are also involved in our synthesis system. The magnetic properties of these nanoparticles are dependent on many factors such as shape and surfactant ligand. Hence, SQUID measurement is conducted to observe zero-field-cooling and field-cooling processes that are mentioned to discuss the magnetic nanoparticles behavior in the low temperature.