화학공학소재연구정보센터
Applied Surface Science, Vol.307, 306-310, 2014
Facile synthesis of oil-soluble Fe3O4 nanoparticles based on a phase transfer mechanism
A stable water-based magnetic fluid was prepared by synthesizing sodium oleate bilayer-coated Fe3O4 nanoparticles via chemical coprecipitation. The adsorption mechanism about excessive sodium oleate coated on particles' surfaces below and above the isoelectric point of Fe3O4 colloid was proposed. Based on this, a novel and facile phase-transform method to transform hydrophilic particles to lipophilic ones has been schemed by adjusting pH value or adding ethanol. The results showed two different transformation mechanisms. In the acid precipitation method, the bilayer-coated structure was retained, which made the hexane magnetic fluid more stable. (C) 2014 Published by Elsevier B.V.