Ultraviolet pulsed laser irradiation of multi-walled carbon nanotubes in nitrogen atmosphere
Laser irradiation of randomly oriented multi-walled carbon nanotube (MWCNT) networks has been carried out using a pulsed Nd:YAG UV laser in nitrogen gas environment. The evolution of the MWCNT morphology and structure as a function of laser fluence and number of accumulated laser pulses has been stu...
| Authors: | , , , , |
|---|---|
| Format: | article |
| Publication Date: | 2014 |
| Country: | España |
| Institution: | Universitat Autònoma de Barcelona |
| Repository: | Dipòsit Digital de Documents de la UAB |
| Language: | English |
| OAI Identifier: | oai:ddd.uab.cat:232157 |
| Online Access: | https://ddd.uab.cat/record/232157 https://dx.doi.org/urn:doi:10.1063/1.4864776 |
| Access Level: | Open access |
| Keyword: | High temperature High temperature annealing treatments Laser fluences Morphology and structures Nitrogen atmospheres Nitrogen gas Thermal simulations Ultraviolet pulsed lasers |
| Summary: | Laser irradiation of randomly oriented multi-walled carbon nanotube (MWCNT) networks has been carried out using a pulsed Nd:YAG UV laser in nitrogen gas environment. The evolution of the MWCNT morphology and structure as a function of laser fluence and number of accumulated laser pulses has been studied using electron microscopies and Raman spectroscopy. The observed changes are discussed and correlated with thermal simulations. The obtained results indicate that laser irradiation induces very fast, high temperature thermal cycles in MWCNTs which produce the formation of different nanocarbon forms, such as nanodiamonds. Premelting processes have been observed in localized sites by irradiation at low number of laser pulses and low fluence values. The accumulation of laser pulses and the increase in the fluence cause the full melting and amorphization of MWCNTs. The observed structural changes differ from that of conventional high temperature annealing treatments of MWCNTs. |
|---|