A new method to synthesize nickel carbide (Ni3C) nanoparticles in solution

Pure nickel carbide (Ni3C) nanoparticles with particle diameters of 40 nm have been prepared by thermal decomposition of nickel formate in the presence of oleic acid and oleyl amine. The coexistence of active nickel and active carbon plays an important role in the formation of metastable Ni3C. Ni3C powder decomposes at 770 K in an N2 atmosphere to yield nickel and carbon. While in an H2 atmosphere, Ni3C powder is converted into Ni at 627 K. In addition, Ni3C nanoparticles exhibit superparamagnetism and are easier to magnetize at room temperature due to their good crystallinity and few defects.