Kinetics of carbon nanotube oxidation

Carbon nanotubes, graphite and amorphous carbon are structurally different, which is reflected in their reactivity and the resistance to oxidation. This paper reports the stability of single- and multi-walled nanotubes, and their true oxidation rates based on conversion to CO₂ when heated in the presence of oxygen. Non-isothermal techniques were employed to determine the kinetic parameters for the oxidation of nanotubes, amorphous carbon and graphite. Single-walled nanotubes were found to be the most reactive, followed by multi-walled nanotubes, amorphous carbon and graphite. The oxidation rates of different single-walled tubes samples containing different residual catalysts were also found to vary significantly.