Preparation of Nickel Powders by Spray Pyrolysis of Nickel Formate

The preparation of nickel powders by the ultrasonic spray pyrolysis of Ni(HCOO)₂ was studied. Phase-pure nickel powder was obtained at as low as 350°C. HCOOH was a reducing source for nickel formation. Moreover, metallic nickel was obtained at a residence time as short as 0.1 s at 600°C. A broad range of particle morphologies, which included agglomerated nanoparticles, nonagglomerated submicrometer particles, hollow particles, and spherical dense particles, were obtained from Ni(HCOO)₂ pyrolysis and were shown to depend on the precursor solution and the operating condition.