Characterization of Nickel Ultrafine Particles Produced by Spraying Method of Nickel Acetate Tetrahydrate Solution into RF Plasma

Nickel ultrafine particles (UFPs) produced by spraying method of nickel acetate tetrahydrate solution into an RF plasma have been characterized. Specific surface area of UFPs, Sw, depended on the liquid feeding rate, JL, and their relation was described as Sw=fJ-nL, where f and n were the constants determined experimentally. Brownian coagulation mechanism as one of UFPs formation mechanisms was discussed based on the value of index n determined from the experiments. Particle diameter of UFPs measured from TEM photographs was expressed by a log-normal distribution with the geometrical standard deviation of smaller than 2.