Laser Irradiation-Hindered Growth of Small-Diameter Single-Walled Carbon Nanotubes by Chemical Vapor Deposition

Abstract EN

SWNTs are synthesized on a Co/MgO catalyst using “laser-disturbed” CVD with CO as the carbon source.

Compared with SWNTs grown by thermal CVD without laser irradiation (normal CVD), SWNTs synthesized under laser irradiation demonstrate the suppression of small-diameter SWNT growth, as indicated by Raman spectroscopy.

Such a phenomenon is also observed for other supported catalysts, such as Co/SiO2 and Fe/MgO.

Controlled experiments were carried out to clarify the effects of lasers.

On the one hand, laser irradiation increases the reaction temperature locally, favoring the growth of SWNTs at a set temperature as low as 350°C.

On the other hand, laser irradiation inhibits the nucleation of small SWNT caps, leading to the growth of large-diameter SWNT species.

This work opens a new avenue for growing SWNTs with controlled diameters.