AVS 51st International Symposium
    Plasma Science and Technology Monday Sessions
       Session PS-MoP

Paper PS-MoP5
RF-plasma Functionalization of Large Quantity of Carbon Nanotubes: XPS and AFM Analysis of O2 and CF4 Treatments

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: A. Felten, LISE, Belgium
Authors: A. Felten, LISE, Belgium
C. Bittencourt, LISE, Belgium
S. Cuenot, Universite Catholique de Louvain, Belgium
R. Daussin, Universite Catholique de Louvain, Belgium
C. Bailly, Universite Catholique de Louvain, Belgium
J.-J. Pireaux, LISE, Belgium
Correspondent: Click to Email
Polymer based electromagnetic screening materials are highly requested nowadays. The fabrication of this material can be achieved by mixing conductive additives to a polymer matrix. CNT are promising ones due to their unique properties. However the formation of homogeneous composite with as grown nanotubes presents a technological difficulty, due to a low compatibility between macromolecules and CNT. To overcome this problem a modification of nanotubes surface by changing their chemical composition was proved to be efficient. There are several ways to modify the CNT surfaces (chemical, plasma@footnote 1@@footnote 2@, fluorination,...). In this work we use inductive RF plasma to functionalize the CNT surface. The nanotubes are Multiwalled prepared by CVD (Nanocyl) and arc discharge (Mercorp). The influence of different plasma conditions (type of gas, power, treatment time, pressure, position of the sample in the discharge) on the functionalization of the CNT was analyzed by XPS. The obtained results show that the concentration of the functional groups bonding at the nanotube surface increased with the treatment time and the plasma power. Concerning the treatment by O2 plasma, the presence of hydroxyl and carboxyl groups has been confirmed by XPS analysis. Depending on the CF4 plasma conditions, it is possible to have either a functionalization of the CNT or a polymerisation of the monomer on the CNT surface. The treatment was scaled up to produce up to 2 grams of nanotubes at once by using magnetic stirring of the powder.An important step of this work was to define the optimal plasma conditions for which the concentration of the fixed functional groups was highest without destruct the nanotube surface. In this way, different plasma treatments were tested on the nanotubes and their surfaces were systematically characterized by atomic force microscopy (AFM).This work is supported by a grant from Region wallone, RW-ENABLE. @FootnoteText@ @footnote 1@H. Bubert et al., Diamond and Related Materials, Vol 12, 3-7, 811-815 (2003)@footnote 2@N. O. V. Plank et al., Applied physics letters, Vol 83, 12, 2426-2428 (2003).