γ-Radiation synthesis of nanocrystalline nickel powder from nickel (II) -ammonia complex solution

摘要

NANOCRYSTALLINE nickel is very important for its applications in the fields such as catalysis and magnetic materials. The usual method used for preparing nanocrystalline nickel is inert gas e-vaporation, which requires high temperature. However, hightemperature easily leads to the growth or oxidation of nickel particles. Marignier et al. reported the nickel microaggre-gates dispersed in solution produced by γ-ifradiating a dilute solution of Ni~(2+) ions (10~(-3) mol/L), which was acidulous in thepresence of polyvinylalcohol and isopropanol. However, nickel particles produced in solution were readily oxidized, especially when exposed to air. Thus the yield of nickel was very low and the preparation and characterization had to be carried out in an inert atmosphere.