Morphology-directing transformation of carbon nanotubes under the irradiation of pulsed laser with different pulsed duration

Abstract

Carbon nanowires have many interesting properties in electronic, opto-electronic and nanoelectromechanical devices due to their high aspect ratios. Carbon nanotubes are ideal templates for the synthesis of one-dimensional carbon nanowires. T-carbon nanowires have been recently produced by the pseudo-topotactic conversion of multi-walled carbon nanotubes (MWCNTs) under picosecond laser irradiation. There is no data about the relationship between the carbon product morphology and laser pulse duration reported so far. Pulsed laser induced reaction is a fast and far from equilibrium process. Carbon nanostructures with different morphology have been produced from carbon nanotube suspension in methanol under laser irradiation with different pulse duration. Carbon nanoparticles, porous carbon nanorods, and even diamond nanobundles have been obtained under nanosecond laser irradiation. The one-dimensional template growth from MWCNTs to carbon nanowires is not successful under nanosecond laser irradiation. However, different carbon nanowires with diameters similar to shortened carbon nanotubes have been easily produced from carbon nanotube suspension under the irradiation of picosecond and femtosecond pulsed laser. The morphology-directing transformations of carbon nanotubes have also explained using reported mechanisms.