Monodisperse cobalt nanoparticles were synthesized by high-temperature reduction of solution-phase cobalt chloride in the presence of a pair of surfactants, oleic acid and triphenylphosphine. Highly ordered two-dimensional superlattices of passivated cobalt nanoparticles were formed by a self-assembly technique. Analysis by X-ray diffraction, UV-vis absorption spectroscopy and transmission electron microscopy demonstrated that the size of the cobalt nanocrystals could be tuned by tailoring the concentration ratio of the two surfactants. In addition, the influence of different crystal sizes on magnetic properties of Co nanocrystals was also investigated.

Large-scale silver nanowires with controlled aspect ratio were synthesized via reducing silver nitrate with 1, 2-propanediol in the presence of poly (vinyl pyrrolidone) (PVP). Scanning electron microscopy, transmission electron microscopy and x-ray powder diffraction were employed to characterize these silver nanowires. The diameter of the silver nanowires can be readily controlled in the range of 100 to 400 nm by varying the experimental conditions. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy results show that there exists no chemical bond between the silver and the nitrogen atoms. The interaction between PVP and silver nanowires is mainly through the oxygen atom in the carbonyl group.

Non-polished aluminum sheets were anodized and the coexistence of self-assembled stripes and porous arrays on the Al surface was observed. The narrostructures were investigated in details using an atomic force microscope. And the formation mechanism of the stripes was discussed and simulated using Brusselator model in this work. We demonstrated that the self-assembled patterns on the Al surface were governed by the competition of formation and dissolution of alumina film during the reaction process. Moreover, this type of ordered structure could only form in certain conditions.

The monodisperse magnetic cobalt nanocrystals(NCs) of 7 nm in diameter were prepared by using high temperature solution phase reducing method. The UV-Vis spectrum showed that the cobalt NCs was stable. The structure of the cobalt NCs were determined by XRD. The results showed that each of the cobalt nanoparticles is a single crystal with a complex cubic structure relating to the beta phase of manganese. The XPS spectra indicate that the surface of Co nanoparticles was not oxidized or formed other compound. Two-dimensional order superlattices of the Co nanoparticles were formed by self-assembly technique.

Monodisperse cobalt nanoparticles are produced by high-temperature thermal decomposition method. The influence of the size of nanoparticles, evaporation temperature, organic solvent, and concentrations on the formation of the cobalt nanoparticles array is studied by transmission electron microscopy and. ultraviolet absorption. Preliminary results of the cobalt nonoparticles magnetic, properties are presented., These results lay a good foundation for the further study of the physical properties and the application in nanoscale devices of magnetic nanoparticles.

Two- and three-dimensional superlattices of passivated cobalt nanoparticles were formed by a self-assembly technique. The size and stabilization of the cobalt nanoparticles are controlled by using the combination of oleic acid and triphenylphosphine. The cobalt nanoparticles are stable for at least 90 days without oxidation at room temperature under ambient conditions. The magnetic properties of the cobalt nanoparticles in different forms are compared, which provides helpful information on the magnetostatic interaction of the nanoparticles.

Synthesis of monodisperse Cobalt nanocrystals by high temperature diol reduction methods in the presence oleic acid and triocethylphosphine stabilizers were reported.The mean size of the Co nanocrystals is about 14±19nm and a standard deviation of the diameter is less than 2%.The structure and the surface valency state of the Co nanocrystals were measured by XRD,Uv-vis,XPS and TEM.The monodisperse Cobalt nanocrystals can be assembled to form a two-dimensional hexagonal close-packed structure.

Long-chain n-octadecayl mercaptan (C18H37SH)-passivated palladium nanoparticles are synthesized and characterized. The palladium nanoparticles are successfully capped by n-octadecayl mercaptan. These palladium nanoparticles have the same face-centered cubic crystalline structure as Pd in the bulk phase. The size of the capped palladium nanoparticles varies in the range of 1.3–5.5 nm for various reaction conditions. These results show that the long-chain n-octadecayl mercaptan-capped palladium nanoparticles are more stable than alkanethiolate-capped Pd nanoparticles with a shorter chain.

Magnetic colloids of cobalt nanocrystals (NCs) were prepared by reducing solute cobalt chloride in the presence of stabilizing agents at a high temperature. The nanocrystalline samples were nearly monodisperse with narrow size distribution of about 7%. X-ray diffraction result showed that Co NCs had a third distinct crystal structure related to the beta phase of manganese. A red shift of the maximum absorption peak of the UV-visible spectra occurred with the increasing diameter of particles, which indicated that we could coarsely control average particle size by adjusting the concentration ratio of cobalt to surfactants. The size of these NCs samples was uniform enough to self-assemble into close-packed and ordered NCs