Soft cutting of single-wall carbon nanotubes by low temperature ultrasonication in a mixture of sulfuric and nitric acids

Abstract

To decrease single-wall carbon nanotube (SWCNT) lengths to a value of 100-200 nm, aggressive cutting methods, accompanied by a high loss of starting material, are frequently used. We propose a cutting approach based on low temperature intensive ultrasonication in a mixture of sulfuric and nitric acids. The method is nondestructive with a yield close to 100%. It was applied to cut nanotubes produced in three different ways: gas-phase catalysis, chemical vapor deposition, and electric-arc-discharge methods. Raman and Fourier transform infrared spectroscopy were used to demonstrate that the cut carbon nanotubes have a low extent of sidewall degradation and their electronic properties are close to those of the untreated tubes. It was proposed to use the spectral position of the far-infrared absorption peak as a simple criterion for the estimation of SWCNT length distribution in the samples.

The role of steam treatment on the structure, purity and length distribution of multi-walled carbon nanotubes

“…Most shortening and cutting strategies take place via a progressive introduction of defects/functionalities into the wall structure until a complete cutting is achieved [52,53]. TGA.…”

Shielding effects in thin films of carbon nanotubes within microwave range

“…Short-length CNTs were produced by cutting long-length CNTs using the procedure detailed elsewhere [18]. Atomic force microscopy (AFM, Solver P47 PRO, NT-MDT Inc) showed that intensive ultrasonication in an acid mixture (95% H 2 SO 4 and 59% HNO 3 at volume fractions of 8:1, respectively) at low temperature (<8 °C) allowed reducing the CNT length down to 100-300 nm for all kinds of tubes, without a significant change of their diameter distribution or modification of their electronic properties (Fig.…”

Nanovector formation by functionalization of TRAIL ligand on single-walled carbon nanotube: Experimental and theoretical evidences

“…These two steps are repeated once at temperature less than 35°C. The resulting suspension is then diluted with water and the SWCNT-COOH nanotubes, collected through 0.2 μm PTFE membrane, washed with water until pH neutral, dried under vacuum for 2h, and the cutting procedure was verified using TEM imagery [15,16].…”