Synthesis of magnetic particles via a cationic–anionic surfactant vesicle method

Abstract In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide–sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe 3+ and Fe 2+ ) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.