One-pot synthesis of uniform and spherically assembled functionalized MFe2O4 (M = Co, Mn, Ni) nanoparticles

A simple versatile one-pot method has been developed for the synthesis of monodisperse, amine functionalized, superparamagnetic, inverse spinel MFe2O4 (Co, Mn, Ni) nanoparticles of size 35-50 nm. TEM image at high magnification shows that each nanoparticle is a discrete spherical assembly of ultrafine particles of size 4-5 nm. The synthesis process was accomplished by refluxing metal chloride precursors in ethylene glycol in presence of sodium acetate and ethanolamine. All three ferrite nanoparticles prepared show superparamagnetism at room temperature with high saturation magnetization. The ZFC and FC magnetization behaviors also supported their TEM microstructure. Due to high surface area, high density of surface amine groups and good aqueous dispersion stability these ferrite nanoparticles may serve as potential alternatives in biomedical applications. (C) 2011 Elsevier B.V. All rights reserved.