Spontaneous dissolution of ultralong single- and multiwalled carbon nanotubes.
We report that chlorosulfonic acid is a true solvent for a wide range of carbon nanotubes (CNTs), including single-walled (SWNTs), double-walled (DWNTs), multiwalled carbon nanotubes (MWNTs), and CNTs hundreds of micrometers long. The CNTs dissolve as individuals at low concentrations, as determined by cryo-TEM (cryogenic transmission electron microscopy), and form liquid-crystalline phases at high concentrations. The mechanism of dissolution is electrostatic stabilization through reversible protonation of the CNT side walls, as previously established for SWNTs. CNTs with highly defective side walls do not protonate sufficiently and, hence, do not dissolve. The dissolution and liquid-crystallinity of ultralong CNTs are critical advances in the liquid-phase processing of macroscopic CNT-based materials, such as fibers and films.
Parra-Vasquez
A Nicholas G
AN
Department of Chemical and Biomolecular Engineering, The Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, TX 77005, USA.
Behabtu
Natnael
N
Green
Micah J
MJ
Pint
Cary L
CL
Young
Colin C
CC
Schmidt
Judith
J
Kesselman
Ellina
E
Goyal
Anubha
A
Ajayan
Pulickel M
PM
Cohen
Yachin
Y
Talmon
Yeshayahu
Y
Hauge
Robert H
RH
Pasquali
Matteo
M
D037742:Nanotubes, Carbon / Q000737:chemistry*; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry
D037742:Nanotubes, Carbon; D012997:Solvents; D013451:Sulfonic Acids; C013880:chlorosulfonic acid