Effect of Surfactants on the Shape of Iron Oxide Nanoparticles Synthesized by Thermal Decomposition

Superparamagnetic iron oxide nanoparticles are one of the most promising materials for biomedical applications. However, despite the large number of researches done on spherical nanoparticles, there is much less work on the effect of particle shape of these nanoparticles on their magnetic properties and biomedical applications. In this work, iron oxide nanoparticles were synthesized using thermal decomposition of iron acetylacetonate in the presence of a mixture of oleyl amine and oleic acid. The XRD measurements show that the nanoparticles have a pure Fe3O4 phase. TEM images show that by changing the ratio of oleic acid to oleyl amine from 0.6 to 1, 1.1 and 1.3 the nanoparticle’s shapes change from spheres to cubes, octopods and rods, respectively; when the ratio is increased to more than 1.3, the nanoparticles start to form spherical shape again. The size of each of these shapes can be precisely controlled by adjusting the time and temperature of the reaction. Magnetic properties and hyperthermia measurements of these samples will be presented and discussed in the meeting.