Gasification behavior of carbon nanotubes

Carbon nanotube-containing carbonaceous materials were gasified in a thermo-balance. The gasification was carried out in 1 vol% oxygen stream at 1023 and 823 K. The gasification behavior of nanotubes was observed using an unique technique, a fixed-point observation technique with a transmission electron microscope. The gasification behavior of carbon nanotubes strongly depended on the gasification temperature. At the gasification temperature of 1023 K, nanotubes were easily gasified at the cracks, defects and strains in the tubes. The destruction from the tip of the tubes was also observed. The gasification rate of the nanoparticles was higher than that of nanotubes. At 823 K, the outer layers of the nanotubes and nanoparticles were disordered with the progress of the gasification and the thin tubes were swelled. The pit formation on the surface of nanotubes was also observed. There was no obvious difference in the gasification rate between nanotubes and nanoparticles in the case of 823 K. (C) 1997 Elsevier Science Ltd.