The Effect of Precursors on the Preparation of Ultrafine Nickel Powder by using Supercritical Methanol

Abstract:

Nickel power was synthesized using supercritical methanol with different nickel precursors (NiO, Ni(CH3COO)2, Ni(NO3)2). The impacts of temperature, pressure, reaction time, and kinds of precursors on the preparation of nickel, were investigated. XRD and SEM were applied to analyze the composition and morphology of the synthesized products. Results showed that the reducing capacity of supercritical methanol was enhanced obviously with the increasing of temperature and pressure. In the reaction system, methanol both played roles of reaction medium and reducing agent. In addition, it was known by studying the influence of precursor kinds on the process that the kind of precursor had a great effect on the preparation of ultrafine nickel. Pure ultrafine nickel could be obtained at the supercritical methanol of 250 ℃, 9 MPa using Ni(CH3COO)2 as precursor. While more higher temperature (280 ℃) and pressure (14.0 MPa) were needed for Ni(NO3)2. When NiO was used as precursor, the mixture of Ni and NiO was obtained even at the more drastic condition of 300 ℃ and 20 MPa.