Physical Properties of Nanotube Materials

Abstract

In this work, carbon nanotube (CNT) yarns were prepared and annealed at temperatures up to 2700 °C in Ar atmosphere. Raman spectroscopy showed a four fold increase in the relative CNT crystallinity after annealing to 2700 °C. The thermal and electrical conductivities of yarns with annealing temperature of 2300 °C and 2700 °C and diameters between 35 to 60 µm were measured as a function of temperature. Both conductivities increased by over 200 % at 300 K after annealing. Other properties studied include IV-curves, magnetoresistance, and the effects of adsorbed oxygen and water.

In addition, the thermal conductivities of various boron nitride nanotube materials were measured, and initial measurements were carried out for the thermal conductivities of ~10 µm reactor-spun CNT fibres.