Solid State Phenomena Vols. 121-123

Abstract: Nanoscaled fibrous aggregates of gold nanoparticles have been synthesized by a simultaneous reduction-oxidation polymerization process using aniline as reducing agent as well as monomer in an ethanol medium. Time-dependent UV-Vis absorption spectroscopy was used to track the formation process of gold nanoparticles. The transmission electron microscopy (TEM) images and Fourier transform infrared (FT-IR) spectrum of the as-preapred products indicate these gold nanoparticles were binded by the oxidation polymerization resultant of aniline.

Abstract: A room temperature route for doping silica particles with Cu nanoparticles to achieve hybrid structures is introduced. First, silica nanoparticles were synthesized according to the well-known Stöber method by hydrolysis and condensation of TEOS in a mixture of ethanol with water, using ammonia as catalyst to initiate the reaction. These SiO2 nanoaprticles were dried at 100 oC. We measured the size of these nanoparticles with transmission electron microscopy (TEM). Second, Cu-SiO2 nanoparticles were synthesized by reaction with CuCl2 and SiO2 nanoparticles in presence of catalyst at room temperature for 12 hrs. Results show silica nanoparticles of about 70 nm size with regularly deposited Cu nanoparticles. Cu-SiO2 nanoparticles were investigated with TEM images, energy dispersive X-ray analysis (EDX) spectrum and so on.

Abstract: A continuous C70 nanowire arrays are prepared using a simple electrophoretic deposition method, composed of two steps: generation of the cluster; and deposition of cluster in the alumina membrane, which is proved to be a practicable technique to fabricate other fullerene low-dimensional nanostructures.

Abstract: The microstructures and properties of (Tb,Sm)CoSi/Cr series films have been investigated. All the samples were sputtered and annealed at 500 °C for 25 min in pure N2 atmosphere, and their microstructures and properties were examined. The effect on the magnetic properties of partial Sm substituted by Tb is discussed. The lattice matching media were examined. And the mechanisms of interactions among the grains and between the magnetic layers have been analyzed by comparing multi magnetic layer with the mono magnetic layer.

Abstract: Cuprous oxide and related materials in nanosizes are of much interest and investigated extensively recently. It is reported here that cubic Cu2O nanocubes were synthesized successfully in aqueous solutions at room temperature in air condition. Copper (II) salts in water were reduced with ascorbate acid in air, using the nonionic pluronic amphiphilic triblock copolymer EO20PO70EO20 (P123) as the template-directing and protecting agent. The average edge length of the cubes varied from 50 to 100 nm. Transmission electron microscopy (TEM) has been used for the shape and structural characterization of the obtained Cu2O nanocubes. The UV-Vis spectra showed an obvious blue-shift (0.53 eV), compared to the band gap of the bulk Cu2O crystal, which makes it a promising candidate in solar energy conversion since this sample can make use of higher energy visible rays of solar spectrum. In the FT-IR spectra the peak of Cu-O bond for the Cu2O is clearly distinguished and several weak peaks of the C-H, C-C and C=O bonds for the organic species can also be detectable, implying a little P123 residua in the products. The effect of the triblock copolymer P123 on the growth of the Cu2O nanocubes is discussed.

Abstract: Nd-Fe-B nanoparticles was prepared by coprecipitation method in aqueous solution. The parameters for the composition are the concentration of borohydride solution and the pH of the solution containing metal ion. The B and Nd contents were found to vary with pH and borohydride concentration. The crystal structure of the synthesized nanoparticles was identified with X-ray powder diffraction (XRD). The size and shape of nanoparticles were confirmed by transmission electron microscope (TEM). The magnetization curves of nanoparticles and nanocomposite were characterized with vibrating sample magnetometer (VSM). Energy dispersive X-ray spectrometer (EDS) was used to characterize composition of Nd-Fe-B nanoparticles.