Cutting Methods and Perspectives of Carbon Nanotubes

Abstract

Short carbon nanotubes have a large potential application value in medicine, electronic devices, and composites. Nevertheless, the length of carbon nanotubes prepared is inconsistent and long, which limits the application range of carbon nanotubes. To cope with this problem, different cutting methods are used to fabricate short carbon nanotubes, which greatly improves the application of carbon nanotubes. Recently, much literature had described the cutting methods of these short carbon nanotubes. Here we attempt to sort out and summarize the relevant literature and highlight the most important advances in cutting methods and machining quality of carbon nanotubes. Special attention is paid to the most common and important physical cutting, chemical cutting, and physical/chemical cutting methods. Significantly, the physical chemistry processes of cutting single-walled carbon nanotubes and multiwalled carbon nanotubes are reviewed and discussed. Additionally, a summary chart is given for readers to understand the cutting methods, application fields, and cutting quality assessments of carbon nanotubes. These can enable researchers in this field to have a deeper understanding of the physical-chemical knowledge and application fields involved in the cutting process of carbon nanotubes. Finally, the conclusions of this paper are summarized, and the current technical challenges and future research opportunities of cutting methods based on carbon nanotubes have been prospected.

Superhydrophobic and Low Reflectance Carbon Nanotubes Buckypapers

“…As one can observe, there are no visual differences between the samples prepared with different sonication energies. The use of surfactant accounts for this behavior, which is attributed to "the unzippering effect" 39 . During the ultrasonic dispersion process, the agglomerations of carbon nanotubes break due to the impact of longitudinal waves (compression and decompression zones).…”

Efficient fabrication of single-wall carbon nanotube nanoreactors by defect-induced cutting

“…The yield is calculated to be 75% (for details see the ESI †) when the average length of the c-SWCNTs is 175 nm, which is higher than most published results. 20,42 However, some long SWCNTs are also observed, which can be attributed to the presence of SWCNT bundles. Furthermore, due to the resolution limitation of AFM characterization, some ultrashort c-SWCNTs were not detected, and the yield could be even higher than the calculated results.…”

“…Therefore, great efforts have been devoted to obtaining short-cut CNTs with open ends. 19,20 Physical cutting and chemical oxidation techniques have been developed to cut CNTs to a length of several hundred nanometers. Physical cutting methods break the walls of CNTs by introducing external forces and energy, such as ball milling, [21][22][23] photolithography, 24 vortex fluidic devices with a pulsed laser, 25 ultra-microtome, 26 ultra-sonication, 27 and electron beam irradiation.…”

Influence of CNT Length on Dispersion, Localization, and Electrical Percolation in a Styrene-Butadiene-Based Star Block Copolymer

“…To shorten CNTs, various strategies have been reported and were summarized in the review of Dai and Wang [19], for example: physical methods such as ball milling, ultramicrotome, or high impact; chemical cutting by the use of oxidizing chemicals which break the carbon bonds; and electrical cutting methods such as electron beams or Jule heat. Raston and coworkers found another interesting method to shorten CNTs in a vortex fluid device under continuous flow conditions using laser irradiation, where the lengths can be controlled via laser pulse energy [20][21][22].…”