Ferrocene's double act

Bulk quantities of single-walled carben nanotubes can be made by the well-known high-pressure carbon monoxide disproportion process (HiPco). this ethod produces SWNT's by flowing a gaseous mixture of carbon monoxide and a samll amount of an iron catalyst through a reactor at high temperature. Now, reachers at the Leibniz Institut in Dresden Germany and the universität Autonoma de Barcelona in Spain have shown that a single compound can serve as the carbon cource as well as the catalyst. Amelia Barreiro and co-workers flowed a misture of gaseous argon and ferrocene through a heated reactor. At temperatures exceeding 500" C. ferrocene spontaneously decomposed into iron clusters and reactive carbon fragments. The metal clusters acted as nucleating agents onto which the carbon atoms grew into SWNT's. Electron microscopy images showed the samples were mainly long bundles of SWNT with diameters between 20-30 nm. Futher characterization using spectroscopic methods confirmed that the material was very similar to those made using the standar HiPco procedure. From J. Phys and Chemestry B. 110 And Nature nanotecnology Vol.1