A method and structure for making
magnetite nanoparticle materials by mixing iron salt with
alcohol,
carboxylic acid and amine in an
organic solvent and heating the mixture to 200–360 C is described. The size of the particles can be controlled either by changing the iron salt to acid / amine ratio or by
coating small nanoparticles with more
iron oxide.
Magnetite nanoparticles in the size
ranging from 2 nm to 20 nm with a narrow size distribution are obtained with the invention. The invention can be readily extended to other
iron oxide based
nanoparticle materials, including M Fe2O4 (M=Co, Ni, Cu, Zn, Cr, Ti, Ba, Mg)
nanomaterials, and
iron oxide coated
nanoparticle materials. The invention also leads to the synthesis of
iron sulfide based nanoparticle materials by replacing
alcohol with
thiol in the reaction mixture. The
magnetite nanoparticles can be oxidized to γ-Fe2O3, or α-Fe2O3, or can be reduced to bcc-Fe nanoparticles, while iron
oxide based materials can be used to make binary
iron based metallic nanoparticles, such as CoFe, NiFe, and FeCoSmx nanoparticles.