Open AccessThis article is
- freely available
Selective Grafting of Primary Amines onto Carbon Nanotubes via Free-Radical Treatment in Microwave Plasma Post-Discharge
Center of Innovation and Research in Materials & Polymers (CIRMAP), Materia Nova Research Center, Parc Initialis, Avenue, N. Copernic 1, B-7000 Mons, Belgium
Center of Innovation and Research in Materials & Polymers (CIRMAP), University of Mons, Place du Parc 20, B-7000 Mons, Belgium
* Authors to whom correspondence should be addressed.
Received: 1 December 2011; in revised form: 6 January 2012 / Accepted: 10 January 2012 / Published: 30 January 2012
Abstract: A novel strategy to graft functional groups at the surface of carbon nanotubes (CNTs) is discussed. Aiming at grafting nitrogen containing groups, and more specifically primary amine covalent functionalization, CNTs were exposed under atomic nitrogen flow arising from an Ar + N2 microwave plasma. The primary amine functions were identified and quantified through chemical derivatization with 4-(trifluoromethyl)benzaldehyde and characterized through X-ray photoelectron spectroscopy. The increase of the selectivity in the primary amines grafting onto CNTs, up to 66.7% for treatment of CNT powder, was performed via the reduction of post-treatment oxygen contamination and the addition of hydrogen in the experimental set-up, more particularly in the plasma post-discharge chamber. The analyses of nitrogenated and primary amine functions grafting on the CNT surface suggest that atomic nitrogen (N•) and reduced nitrogen species (NH• and NH2•) react preferentially with defect sites of CNTs and, then, only atomic nitrogen continues to react on the CNT surface, creating defects.
Keywords: carbon nanotubes; atomic nitrogen; primary amine grafting; microwave plasma; XPS
Citations to this Article
Cite This Article
MDPI and ACS Style
Ruelle, B.; Peeterbroeck, S.; Godfroid, T.; Bittencourt, C.; Hecq, M.; Snyders, R.; Dubois, P. Selective Grafting of Primary Amines onto Carbon Nanotubes via Free-Radical Treatment in Microwave Plasma Post-Discharge. Polymers 2012, 4, 296-315.
Ruelle B, Peeterbroeck S, Godfroid T, Bittencourt C, Hecq M, Snyders R, Dubois P. Selective Grafting of Primary Amines onto Carbon Nanotubes via Free-Radical Treatment in Microwave Plasma Post-Discharge. Polymers. 2012; 4(1):296-315.
Ruelle, Benoit; Peeterbroeck, Sophie; Godfroid, Thomas; Bittencourt, Carla; Hecq, Michel; Snyders, Rony; Dubois, Philippe. 2012. "Selective Grafting of Primary Amines onto Carbon Nanotubes via Free-Radical Treatment in Microwave Plasma Post-Discharge." Polymers 4, no. 1: 296-315.