Effect of organic molecules absorption in the magnetic properties of iron oxide nanoparticles

The magnetite nanoparticles and magnetite capped with oleic acid or oleylamine from a biphase water/toluene solution was synthesized in different starting temperatures. It was observed that the higher the temperature at the beginning of the reaction the smaller the mean size of the nanoparticles, which is attributed to the simultaneous formation of more nuclei. Besides the presence of the surfactants, the crystal growth was stopped thus forming smaller nanoparticles. Also the exact shape and size of the nanoparticles was estimated from the TEM micrographs.