Structural investigation of heat-treated fullerene nanotubes and nanowhiskers

In situ heating experiments by use of TEM were performed for the C-60 fullerene nanotubes prepared by the liquid-liquid interfacial precipitation method combined with ultrasonication. The C-60 nanotubes retained their crystalline Structure up to 650 degrees C and began to become amorphous above 700 degrees C. However, the 220 spots of electron diffraction pattern were clearly observed up to 750 degrees C, suggesting that strong bonding forces between C-60 molecules were acting along the tube growth axis. It was found that C-60 nanotubes were more resistant to heating than C-60 nanowhiskers under electron beam irradiations. (c) 2005 Elsevier B.V. All rights reserved.