Solution Synthesis of Nano-Phase Nickel as Film and Porous Electrode

Routes to nano-phase nickel in the forms of highly porous sponges and dense films have been developed. Nickel acetate and nitrate were mixed with triethanolamine and methanol, and evaporated to a concentrated liquid. Heat-treatment at 10°C/min to 170°C under N₂ atmosphere yielded a highly porous sponge consisting of <10 nm sized Ni crystallites. Deposition of a 1 M nickel precursor solution on polycrystalline Al₂O₃, SnO₂ : F coated glass or titanium substrates spinning at 2700 rpm, followed by heat-treatment at 10°C/min to 400°C yielded smooth and dense nickel films consisting of 3–5 nm sized crystallites. The precursor concentrate was studied by FT-IR and the phase development on heat-treatment was studied by thermogravimetric analysis, powder X-ray diffraction, scanning and transmission electron microscopy.