Relation of the Electrical Conductivity and the Thermal Conductivity to the Young’s Modulus of Buckypapers

Abstract

Buckypapers (BPs) are porous films of randomly oriented carbon nanotubes (CNTs), and have potential applications in many fields. To get better performance, the properties of BPs are needed to be tuned to meet the demands of various applications. In this paper, the effects of annealing on tuning the Young’s modulus, the electrical conductivity, and the thermal conductivity of BPs were studied. Our results indicated that the Raman G/D ratio of BPs increased from 0.8 to 3.9 after annealed at 2800 ℃, which indicates that the quality of CNTs has been improved after annealing. The Young’s modulus of the annealed BPs increased linearly with the annealing temperature due to the improvement in the CNT quality, and an increase of 82 % was attained after annealed at 2800 ℃. Furthermore, the electrical conductivity and the thermal conductivity of BPs increased nonlinearly with the annealing temperature, and the increases after 2800 ℃ heat treatment are 29 % and 125 %, respectively. We attributed the increase in both electrical and thermal conductivities to the enhancement of inter-tube contact after the annealing.