Soft Oxidation of Single-Walled Carbon Nanotube Samples
Résumé
Thermal dry oxidation treatment is a straightforward and commonly used technique in carbon nanotube (CNT) processing. Among its advantages, it plays a key role in guaranteeing the efficiency of numerous purification procedures. It also enables a chemical modification of the nanotube surface by covalent bonding of oxygen-containing functions. Nevertheless, a careful optimization of the experimental conditions used for the treatment is a crucial step in order to obtain the desired effect and avoid a strong damaging of the CNTs. Soft oxidation conditions are thus in particular of great interest. We report on the oxidation of CNTs in a large scale of oxidation conditions. The treated samples were characterized using several techniques including transmission electron microscopy, thermal gravimetric analysis, dispersion tests, and Raman spectroscopy to investigate both morphological and surface properties. We were thus able to discriminate between the behavior of the CNTs from that of other carbonaceous species. The problem of the selectivity of the oxidation treatment is especially discussed.