Relationship between the structure of carbon nanocoils and their electrical property

The electrical property of carbon nanocoils (CNCs) annealed from 300 to 2900 K has been studied by a four-probe technique. It was shown that the resistivity of the CNCs decreased with the increase of the annealing temperature owing to the improvement of crystallinity and the most notable change of resistivity occurred at the initial structure change of the CNCs. Besides the measurement of room-temperature resistivity of the annealed CNCs, temperature-dependent resistance of the annealed CNCs was also measured. According to the nearest neighboring hopping mechanism, the average activation energy for electron hopping in the annealed CNCs was calculated, which indicated that the average activation energy reduced with the structural improvement of CNCs. It was also found that the variation of average activation energy was also sensitive to the initial structural change of CNCs. Finally, through studying the electrical property of the CNCs under expansion, it was found that the resistance of the CNC was not changed with elongation. (C) 2014 Elsevier Ltd. All rights reserved.