Preparation of AgNi nanoparticles in microemulsions

摘要

AgNi alloys are the most promising electronic contacted materials due to their optimal combination of the high thermal and electrical conductivity of silver and the high erosion resistance of nickel. However, because of the repulsive interaction of silver and nickel, it is difficult to prepare AgNi alloy with dispersed microstructure by using the traditional methods. Therefore, it is important to find a new method to prepare AgNi alloy. Nanoparticles containing silver and nickel have been prepared by the reduction of AgNO3 and NiSO4 with hydrazine in cyclohexane/n-butanol/SDS/water microemulsions. The chemical composition, morphology, crystal structure, particle size and size distribution of the nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results show that the nanoparticles are perfect crystals with regular sphericity. The mean diameter of AgNi nanoparticles is about 20 nm. In addition, the research shows that the composition of the nanoparticles can be controlled by the primal concentration ratio of silver nitrate and nickel sulfate.