Patent ID: 7357907

Claim:
A method of preferentially forming single walled carbon nanotubes having a particular diameter, comprising: providing a catalyst comprising: Co and Mo disposed on a support material wherein the majority of the Mo occurs as dispersed Mo oxide clusters and the majority of the Co occurs as CoMoO 4 with the Co therein primarily in an octahedral configuration, and wherein the CoMoO 4 occurs substantially disposed upon the dispersed Mo oxide clusters; and exposing the catalyst in a reactor to a carbon-containing gas at a temperature between about 700° C. and about 800° C. and maintaining a CO 2 concentration in the reactor below a threshold CO 2 concentration above which the conversion of ionic Co to metallic Co is inhibited, wherein the majority of the single walled carbon nanotubes thus formed have a diameter between about 0.7 nm to about 0.9 nm.