Patent ID: 8182786

Claim:
A method of preparing metal oxide nanoparticles, comprising: (a) mixing a metal acetate precursor with a non-aqueous organic solvent comprising at least one organic stabilizing ligand to form a reaction mixture; (b) subjecting the mixture of step (a) to a temperature greater than about 100° C. for a time sufficient to allow formation of metal oxide nanoparticles and decomposition of the metal acetate; and (c) extracting the metal oxide nanoparticles into a hydrocarbon solvent at a temperature lower than the temperature of step (b) by precipitation with a flocculating agent; wherein the metal of the metal oxide nanoparticles has an oxidation state that is the same or less than the oxidation state of the metal of the metal acetate precursor, wherein the metal acetate of step (a) is selected from the group consisting of iron (Fe) acetate, manganese (Mn) acetate, cobalt (Co) acetate, ruthenium (Ru), copper (Cu) acetate, scandium (Sc) acetate, titanium (Ti) acetate, vanadium (V) acetate, chromium (Cr) acetate, chromium (Cr) acetate dimer, molybdenum (Mo) acetate, molybdenum (Mo) acetate dimer, yttrium (Y) acetate, zirconium (Zr) acetate, hafnium (Hf) acetate, and nickel (Ni) acetate.