ChemInform Abstract: Nonaqueous Electrodeposition of Niobium from Propylene Carbonate and Acetonitrile

Abstract

Despite its many outstanding properties, including superconductivity, corrosion resistance, and a high melting point, niobium remains one of the most elusive metallic elements for successful electrodeposition under mild conditions. Some factors which may contribute to the difficulty of electrodeposition include a rather negative reduction potential, which leads to interference by hydrogen evolution in aqueous solutions; the tendency of niobium species to react with oxygen or moisture to form electrochemically inactive species, and to even abstract oxygen from certain non-aqueous solvents like dimethylsulfoxide; and the tendency of niobium to form stable cluster compounds at low valent states. current successful methods for electrodeposition involve either high temperature (i.e. > 700/sup 0/C) molten salt electrodeposition in alkali halide mixtures (2-5), or cryogenic electrodeposition from pure liquid halogens, interhalogens, or hydrogen halides, such as HF. The authors report here preliminary results on the electrodeposition of niobium from organic solvents at room temperature. This approach affords two unique advantages. First, it allows a simpler electrochemical cell to be used compared to those used for the corrosive and toxic alkali fluoride melt or the volatile HF. Second, thermally induced lattice disorder may potentially be minimized so that the niobium film may be better suited for technologicalmore » applications.« less