Morphologies and properties of nickel particles prepared by spray pyrolysis

Nickel particles were prepared by spray pyrolysis of aqueous solutions of NiCl₂·6H₂O with reducing gas. Wet pyrolysis lowered the onset and the finishing temperatures of the individual chemical transformations by at least 100°C to contribute high conversion to nickel and its completion of sintering. Densification by increasing the furnace set temperature outweighed the adverse effects of the dry sintering and short residence time of the precursor particles. The initial salt concentration increased the size of the nickel particles with their densification, resulting from the enhanced rate of nickel nucleation.