Metal Fe,Ni and Fe-Ni Fine Fibers Derived from the Organic Gel-Thermal Reduction Process

The organic gel-thermal reduction process was successfully used for the preparation of magnetic metal Ni, Fe, Fe-Ni fine fibers from raw materials of citric acid or lactic acid and metal salts. Ni, Fe and Fe-Ni fine fibers synthesized were featured with diameters of around 1 μm and lengths of as long as 2 m for Ni fibers, 0.5 m for iron fibers, 1 m for Fe-Ni fibers. The structure, thermal decomposition process and morphologies of the gel precursors and fibers derived from thermal reduction of these gel precursors were characterized by FTIR, XRD,TG/DSC and SEM, respectively. The gel spinnability largely depends on molecular structures of metal-carboxylate complexes formed in the gel. It is reasoned that these gels consist of linear-type structural molecules [（C6H6O7）Ni]n or [（C6H5O7）2Ni3] for the nickel citrate gel, [（C3H5O3）3Fe] for the ferric lactate gel, [（C6H5O7）5（NiFe）3] for the iron-nickel citrate gel respectively and the gels obtain showed a good spinning performance.