Iodination of Single-Walled Carbon Nanotubes

Abstract

Iodinated single-walled carbon nanotubes, with iodine covalently bound to the nanotube surface, have been synthesized by oxidation of the carbon nanotubes followed by a modified Hunsdiecker reaction using elemental iodine and iodosobenzene diacetate (IBDA). High-resolution transmission electron microscopy (HRTEM) images show small high-contrast spots which are stable to the electron beam and are assigned to iodine atoms bonded to the surface of the nanotube. Importantly, the electronic properties of the nanotubes were found to be largely intact after functionalization. The iodinated carbon nanotubes were fully characterized using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, UV−vis−NIR spectroscopy, and thermogravimetric analysis−mass spectrometry (TGA-MS).

Interactions Between Amino Acid‐Tagged Naphthalenediimide and Single Walled Carbon Nanotubes for the Design and Construction of New Bioimaging Probes

“…Supramolecular wrapping is rapid and uniform thus bypassing the need for complex covalent synthetic procedures to be performed directly on the SWNT surface. [99][100][101] The new NDI reported hereby is a biocompatible nanoreceptor that may be derivatized further by virtue of the carboxylic groups: our method of SWNTs wrapping will facilitate the rapid incorporation of targeting peptides onto onto SWNTs (whereby the mass ratio of NDI:SWNT was kept at 0.6, consistent with observations from fluorescence titrations) and concentrations ranging from 1 μg/mL to 250 μg/mL for the pristine SWNT. MI 50 values were estimated in each case from five repeat experiments (see Supplementary Information).…”

“…MTT assays suggest that NDI@ SWNTs has a somewhat lower cytotoxicity compared to that of the free SWNTs and free NDI healthy cells (FEK-4) versus in aid the identification by TEM of the uniform coating of the surface of the carbon nanotubes. [3,101] The "host" is tightly wrapped around the carbon nanotube, forming a monolayer of NDI held to the aromatic surface by π-π stacking reinforced by solvophobic effects. The NDI network adapts its geometry in order to accommodate a guest with diameters as wide as 1.6 nm (i.e., a [10,10] SWNT).…”

Functional Covalent Chemistry of Carbon Nanotube Surfaces

“…Specifically, many of these approaches take advantage of the use of carboxylic acid residues immobilized onto SWNTs; in this regard, a recent paper proposed either a direct coupling of ethylenediamine with carboxylic acid groups or reduction of carboxyl groups to hydroxymethyl moieties followed by a subsequent transformation into aminomethyl groups as a means of creating amino-functionalized nanotubes for binding to (i) polymers and (ii) biological systems. [183] It is notable that one can also envision creation of these versatile amide and heteroamide functionalities on nanotube sidewalls using either fluorinated or iodinated SWNTs as a precursor [184,185] and subsequently using these entities as building blocks in copolymerization and polycondensation reactions to create useful nanocomposite structures with enhanced physical properties.…”

Carbon nanotube (CNT)–epoxy nanocomposites: a systematic investigation of CNT dispersion

“…The difficulty in dispersing CNTs arises from their inherently inert (hydrophobic) nature and tendency to agglomerate and entangle due to their size and shape (long hair-like). Reported literature addressing these challenges largely rely on chemical functionalization of CNTs (Suri et al 2008;Coleman et al 2007;Chakraborty et al 2009;Martinez-Rubi et al 2007) which requires expensive chemicals and therefore, is not commercially very attractive considering the cost involved. In addition, use of aggressive chemicals and strong dispersing methods such as prolonged ultrasonication can degrade the CNT intrinsic properties or even cut them shorter (Niyogi et al 2002;Liu et al 1998).…”