Synthesis and electromagnetic absorption properties of micro-nano nickel powders prepared with liquid phase reduction method

Abstract

Monodisperse micro-nano nickel powders have been prepared by chemical reduction of aqueous solution NiSO4, NaOH and NaH2PO2, and the influence of pH value and initial concentration of NiSO4 on the size, structure, morphology and microwave absorption properties of nickel powders were investigated. The crystal structure of nickel powders was characterized by X-ray diffraction (XRD). And the morphology of the as-synthesized products was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The microwave absorption properties of the composite materials were characterized by network analyzer. The result indicates that the growth of nickel powders produced by NiSO4 and NaH2PO2 at alkaline condition deeply relies on pH value and initial concentration of NiSO4 in reaction system. Different sizes of nickel powders with the diameter of 1.5 µm and 180 nm were produced at the pH value of 10 and initial concentration of NiSO4 at 0.5 mol/L. The network analyzer showed definite microwave absorption properties of nickel powders with different sizes in the range of 0.5-18.0 GHz.