Versatile Two-Step Functionalization of Nanocarbons: Grafting of Propargylic Groups and Click Post-Functionalization

Chemical functionalization of nanocarbons is essential for further applications in various fields. We developed a facile, inexpensive, and gram-scale one-pot route towards alkynyl-functionalized nanocarbons. Nucleophilic addition/propargylic capture places alkyne moieties at the surface of carbon nanotubes (CNTs) and graphene. Thermogravimetric analysis coupled with mass spectrometry and Raman analysis confirmed the efficiency of this process. Conductivity measurements demonstrated the maintenance of the CNT electrical properties. The attached alkynyl moieties were reacted with various azide derivatives through the click-Huisgen [3+2] cycloaddition and characterized with XPS. The efficient addition of those derivatives enables the application of our finding in various fields. This route is a reliable and convenient alternative to the known diazonium functionalization and oxidation-esterification reactions to graft alkyne groups.