Preparation Of Metal Nano-structured Material

1,10-Decandiol is used as reducing agent to synthesize magnetic cobalt nanoparticles with the surfactants of oleic acid and ethylene glycol octyl phenyl ether(OP). The structure and the valency state of cobalt nanoparticles are measured by XRD and XPS. The morphology is surveyed by TEM and laser particle size detector respectively. The results show that the cobalt nanoparticles consist of hcp phase and the average size is about 20 nm. To change the preparation conditions, cobalt nanorings are produced for the first time. The outer diameter of the rings is about 65 nm, and the inner one's is near 55 nm.Cobalt salts are reduced to magnetic cobalt nanoparticles by hydrazine reduction method in the ethanol system. The particles are packed by polyvinylpyrrolidone(PVP) to protect oxidation. The results of XRD,XPS, TEM and laser particle sizer detector show that the cobalt nanoparticles consist of hcp phase, and the average size is about 30 nm. The circular grains are dispersed well in the hexane. Changing the surfactant concentration and using the macromolecule PVP as soft template, nanosized cobalt porous rod and nanoscale common cobalt rod are synthesized. The cobalt porous rod consist of both hcp and fcc phases, with the ratio of about 1: 1. The porous rod is about 200~500 nm in length and 20~ 40 nm in diameter. The diameter of the hole is about 8 nm. With the increasing of concentration of cobalt salts, the diameter of the porous rod can reach 40~60 nm. Whereas the length of common cobalt rod is close to 3~4 μm, and the diameter is about 70~ 100 nm. Last, the mechanism of both cobalt porous rod and common rod is discussed simply.Using the same synthesis method and the mechanism of common cobalt rod, we prepare nanosized nickel rod. The nickel rod is approximate 500~650 nm long and the diamension is close to 50 nm, consisting of fcc phase. Meanwhile, nickel,copper and silver spherical nanoparticles are synthesized also using hydrazine reduction method in the ethanol system. The diameter is about 40 nm, 35 nm and 50 nm respectively. All these circular particles are dispersed well in the hexane.