Control of iron nanoparticles size and shape by thermal decomposition method

iron nanoparticles were prepared by thermal decomposition under 180 degrees C with 0.256 M iron pentacaronyl and 0 M-0.085 M oleylamine as a surfactant. Sizes of the synthesized iron nanoparticles are from 4.8 nm to 10.9 nm depending on the decomposition times in the range from 10 to 60 min. The surfactant concentration is a key factor for controlling the size and shape of iron nanoparticles. The synthesized iron particles without surfactant are flocculated to be clusters of 20-50 nm. In the case of using 0.0425 M surfactant, the obtained particles are almost sphere. While oleylamine concentration was added up to 0.085 M, several iron nuclei are agglomerated together regularly. It is confirmed that the synthesized iron particles are amorphous, but the surface of the particles is easily oxidized and to be spinel structured iron oxide by HRTEM.