Facile ultrafast microwave synthesis of monodisperse MFe2O4 (M=Fe, Mn, Co, Ni) superparamagnetic nanocrystals

A series of metal ferrite nanocrystals MFe2O4 (M=Fe, Mn, Co, Ni) were prepared via a microwave synthesis strategy. The whole synthesis process could be accomplished in a few minutes at a moderate temperature and without inert gas protecting. The resulting products were systematically characterized and showed uniform spherical morphology with an average particle size of 6.0nm, well crystallinity, superparamagnetic property and relatively high saturation magnetization. A microwave heating based classical crystallization mode was proposed for the formation of these nanocrystals. This work sheds new light on the synthesis of magnetic nanoparticles with improved properties through a rapid, “green” microwave-assisted synthesis strategy. A microwave synthesis strategy has been developed for preparing a series of monodisperse metal ferrite nanocrystals, including Fe3O4, MnFe2O4, CoFe2O4 and NiFe2O4, within a few minutes. [Display omitted] •A series of metal ferrite nanocrystals MFe2O4 (M=Fe, Mn, Co, Ni) were prepared via a microwave synthesis strategy.•The microwave synthesis process could be accomplished just in a few minutes at a moderate temperature and without inert gas protecting.•The obtained MFe2O4 (M=Fe, Mn, Co, Ni) were showed uniform spherical morphology with an average particle size of 6.0nm, well crystallinity, superparamagnetic property and relatively high saturation magnetization.•A microwave heating based classical crystallization mode was proposed for the formation of these nanocrystals.