ZnO nanowires were mass produced using a physical vapor deposition approach. The ZnO nanowire monocrystallites have an average diameter around 60 nm and length up to a few micrometers. The unidirectional growth of the ZnO nanowires was controlled by the conventional vapor-liquid-solid mechanism. Intensive UV light emission peaked around 3.27 eV was observed at room temperature, which was assigned to emission from free exciton under low excitation intensity. The observed room temperature UV emission was ascribed to the decrease in structure defects as compared to bulk ZnO materials, and in particularly to the size effect in the ZnO wires.

Ultraviolet-emitting ZnO nanowires synthesized by a physical vapor deposition approach

This paper describes a vapor-phase approach to the facial synthesis of cupric oxide (CuO) nanowires supported on the surfaces of various copper substrates that include grids, foils, and wires. A typical procedure simply involved the thermal oxidation of these substrates in air and within the temperature range from 400 to 700 °C. Electron microscopic studies indicated that these nanowires had a controllable diameter in the range of 30−100 nm with lengths of up to 15 μm by varying the temperature and growth time. Electron diffraction and high-resolution TEM studies implied that each CuO nanowire was a bicrystal divided by a (111) twin plane in its middle along the longitudinal axis. A possible mechanism was also proposed to account for the growth of these CuO nanowires.

CuO Nanowires Can Be Synthesized by Heating Copper Substrates in Air

Aligned Single‐Crystalline Si Nanowire Arrays for Photovoltaic Applications

A novel strategy for preparing large-area, oriented silicon nanowire (SiNW) arrays on silicon substrates at near room temperature by localized chemical etching is presented. The strategy is based on metal-induced (either by Ag or Au) excessive local oxidation and dissolution of a silicon substrate in an aqueous fluoride solution. The density and size of the as-prepared SiNWs depend on the distribution of the patterned metal particles on the silicon surface. High-density metal particles facilitate the formation of silicon nanowires. Well-separated, straight nanoholes are dug along the Si block when metal particles are well dispersed with a large space between them. The etching technique is weakly dependent on the orientation and doping type of the silicon wafer. Therefore, SiNWs with desired axial crystallographic orientations and doping characteristics are readily obtained. Detailed scanning electron microscopy observations reveal the formation process of the silicon nanowires, and a reasonable mechanism is proposed on the basis of the electrochemistry of silicon and the experimental results.

Fabrication of Single-Crystalline Silicon Nanowires by Scratching a Silicon Surface with Catalytic Metal Particles†

One dimensional nanostructured materials

We report the large-scale synthesis of silicon nanowires (SiNWs) using a simple but effective approach. High purity SiNWs of uniform diameters around 15 nm were obtained by sublimating a hot-pressed silicon powder target at 1200 °C in a flowing carrier gas environment. The SiNWs emit stable blue light which seems unrelated to quantum confinement, but related to an amorphous overcoating layer of silicon oxide. Our approach can be used, in principle, as a general method for synthesis of other one-dimensional semiconducting, or conducting nanowires.

Nanoscale silicon wires synthesized using simple physical evaporation

(Received 6 October 2004; accepted 8 October 2004)[DOI: 10.1063/1.1825625]It is found recently that there was an error in two paperswe published in 1998: we mistakenly used the same XRDdata in two papers [Fig. 2(a) in Ref. 1 and Fig. 3 in Ref. 2],which described two different methods for synthesis of sili-con nanowires, whose products have the same morphologyand structure. The authors apologize for possible confusionto the readers that may have arisen from such an error,though it did not change the conclusion of the paper, becauseXRD was not the only means for structure characterization,as Raman and TEM were also used to support our conclu-sion. Moreover, our results have been repeated by our laterwork,

H. T. Zhou

Papers

Nanoscale silicon wires synthesized using simple physical evaporation

Erratum: ¿Nanoscale silicon wires synthesized using simple physical evaporation¿ [Appl. Phys. Lett. 72, 3458 (1998)]