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 β 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.
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.
