Science of single-wall carbon nanotubes: Purification, characterization and chemistry
type: CreativeWork
description: Characterization of raw nanotube materials produced by different methods is demonstrated. Depending on the production methods, tubes of different diameters can be produced. Purification of single wall carbon nanotubes produced by laser-oven and HiPco process is also discussed. Metal catalyzed oxidation at low temperature has been shown to selectively remove non-SWNT carbon and permit extraction of metals with concentrated HCl. These multi-stage purification methods have been investigated and the sample purity is documented by EDAX, ESEM, TGA, Raman and UV-vis-Nir spectroscopy. Covalent attachment of functional groups and molecules, including fluorine, methyl, n-butyl and n-hexyl groups, to the sidewalls of single wall carbon nanotubes has been achieved. Further fluorination study is done to investigate the effect of HF which is used as catalysts. Parallel fluorination experiments are performed on both laser-oven-grown and HiPco SWNTs. Larger diameter tubes, i.e. laser-oven-grown SWNTs, require higher fluorination temperatures. A limiting stoichiometry of C2F can be reach for Fluorotubes. Quantitative measurement of the alkylation was done by thermal gravimetric analysis. A mechanism involving electron transfer and effects of reaction temperature, solvents and steric effects of the alkyl groups are discussed. Prolonged exposure of small diameter SWNT ropes (diameters &lt; 5 nm) to hot fuming sulfuric acid has been shown to grow super-ropes with approximately 10,000 tubes in cross-section from rope sizes of approximately 10 tubes. This represents the largest rope sizes ever seen. Examination of the spectral properties of the SWNTs indicates that the roping occurs without changing the chemical state of the nanotubes. Acid intercalation of single wall carbon nanotubes is examined. Several super acids and strong acids are used to study the charge transfer and protonation effects on SWNTs. The degree of charge transfer is clearly correlated with the ability of acid to int…
abstract: Characterization of raw nanotube materials produced by different methods is demonstrated. Depending on the production methods, tubes of different diameters can be produced. Purification of single wall carbon nanotubes produced by laser-oven and HiPco process is also discussed. Metal catalyzed oxidation at low temperature has been shown to selectively remove non-SWNT carbon and permit extraction of metals with concentrated HCl. These multi-stage purification methods have been investigated and the sample purity is documented by EDAX, ESEM, TGA, Raman and UV-vis-Nir spectroscopy. Covalent attachment of functional groups and molecules, including fluorine, methyl, n-butyl and n-hexyl groups, to the sidewalls of single wall carbon nanotubes has been achieved. Further fluorination study is done to investigate the effect of HF which is used as catalysts. Parallel fluorination experiments are performed on both laser-oven-grown and HiPco SWNTs. Larger diameter tubes, i.e. laser-oven-grown SWNTs, require higher fluorination temperatures. A limiting stoichiometry of C2F can be reach for Fluorotubes. Quantitative measurement of the alkylation was done by thermal gravimetric analysis. A mechanism involving electron transfer and effects of reaction temperature, solvents and steric effects of the alkyl groups are discussed. Prolonged exposure of small diameter SWNT ropes (diameters &lt; 5 nm) to hot fuming sulfuric acid has been shown to grow super-ropes with approximately 10,000 tubes in cross-section from rope sizes of approximately 10 tubes. This represents the largest rope sizes ever seen. Examination of the spectral properties of the SWNTs indicates that the roping occurs without changing the chemical state of the nanotubes. Acid intercalation of single wall carbon nanotubes is examined. Several super acids and strong acids are used to study the charge transfer and protonation effects on SWNTs. The degree of charge transfer is clearly correlated with the ability of acid to int…
author: Chiang, Ivana Wan-Ting
language: eng
keywords: Physical chemistry, Engineering, Materials science
date published: 2001
date modified: 2026-07-24T04:10:32Z
provider: Rice University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Rice University

PropertyValue
property ID: Handle
value: https://hdl.handle.net/1911/17947