Publication
Title
Chirality-dependent densities of carbon nanotubes by in situ 2D fluorescence-excitation and Raman characterisation in a density gradient after ultracentrifugation
Author
Abstract
Density gradient ultracentrifugation (DGU) becomes increasingly important for the sorting of nanomaterials according to the particles' density, hence structure and dimensions, which determine their unique properties, but the further development of this separation technique is hindered by the limited precision with which the densities could be characterized. In this work, we determine these densities by position-dependent 2D wavelength-dependent IR fluorescence-excitation and resonant Raman spectroscopy measured directly in the density gradient after ultracentrifugation. We apply this method to study the diameter and chirality-dependent sorting of empty and water-filled single-walled carbon nanotubes coated with two different surfactants, sodium cholate (SC) and sodium deoxycholate (DOC). The results elucidate the long standing contradiction that SC would provide better diameter sorting, while DOC is the most efficient surfactant to solubilise the nanotubes. A more predictable separation is obtained for empty DOC-coated nanotubes since their density is found to vary very smoothly with diameter. The accurate and chirality-dependent densities furthermore provide information on the surfactant coating, which is also important for other separation techniques, and allow to determine the mass percentage of water encapsulated inside the nanotubes.
Language
English
Source (journal)
Nanoscale / Royal Society of Chemistry [London] - Cambridge
Publication
Cambridge : 2015
ISSN
2040-3364
Volume/pages
7:47(2015), p. 20015-20024
ISI
000365530700020
Full text (Publisher's DOI)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
E-info
Web of Science
Record
Identification
Creation 15.01.2016
Last edited 20.06.2017
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