Honolulu, HI (PRWEB) April 28, 2006
The controllable, large-scale synthesis of SWNT nanorings provides numerous opportunities for investigating transport, electronic and optical phenomena through a nanotubes annular structures. Furthermore, this relatively simple method will provide a promising material (i.e. SWNT nanorings) for the realization of nanometer-scale electric circuits and magnetically induced changes in electronic structure.
Professor Sishen Xie together with first author Dr. Li Song, both from the Institute of Physics at the Chinese Academy of Sciences in Beijing, reported that large scales of nanorings were prepared in a floating catalyst chemical vapor deposition (CVD) system. The rings obtained have a smaller diameter about 100 nm, compared with the rings produced in previous works. Their findings were reported in a recent paper titled “Efficiently producing single-walled carbon nanotube rings and investigation of their field emission properties” in the April 11, 2006 online edition of Nanotechnology.
“We showed that the yield and the quality of nanorings could be further increased with more optimized growth parameters,” Xie explained to Nanowerk. “In the field emission measurements, we found that field emission behavior from a halved SWNT ring is better than that from a whole nanoring, which is contributed to the better emission capability from two opened nanotubes ends of the halved nanoring.”
And as a remarkable advantage for potential applications such as electric devices, the nanorings were deposited at relatively low temperature with wide density range on different substrates. “The sublimation temperature of the catalyst of between 52-58
