Covalent Sidewall Functionalization of SWNTs by Nucleophilic Addition of Lithium Amides

Abstract

Abstract The synthesis and characterization of sidewall‐functionalized SWNT derivatives ( n PrNH) n ‐SWNTs containing n ‐propylamine addends is reported. The nucleophilic addition of in situ generated lithium n ‐propylamide to the sidewall of SWNTs and the subsequent reoxidation of charged intermediates of the type ( n PrNH) n ‐SWNT n – leads to carbon nanotube derivatives with covalently attached amino groups. Based on the reaction sequence, a homogeneous dispersion of the carbon nanotube material is achieved as a result of the electrostatic repulsion of negatively charged intermediates. The solubility of the resulting propylamine‐functionalized ( n PrNH) n ‐SWNT material in organic solvents is drastically increased. The functionalized tubes were characterized in detail by Raman spectroscopy, thermogravimetric analysis (TGA/MS), X‐ray photoelectron spectroscopy (XPS) and UV/Vis/NIR spectroscopy. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)