中国物理B ›› 2012, Vol. 21 ›› Issue (10): 106102-106102.doi: 10.1088/1674-1056/21/10/106102
• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇 下一篇
张凯旺, 李中秋, 吴建, 彭向阳, 谭新君, 孙立忠, 钟建新
Zhang Kai-Wang (张凯旺), Li Zhong-Qiu (李中秋), Wu Jian (吴建), Peng Xiang-Yang (彭向阳), Tan Xin-Jun (谭新君), Sun Li-Zhong (孙立忠), Zhong Jian-Xin (钟建新)
摘要: In this paper, a novel double-wall carbon nanotube (DWCNT) with both edge and screw dislocations is studied by using the molecular dynamics (MD) method. The differences between two adjacent tubule indexes of armchair and zigzag nanotubes are determined to be 5 and 9, respectively, by taking into account the symmetry, integrality, and thermal stability of the composite structures. It is found that melting first occurs near the dislocations, and the melting temperatures of the dislocated armchair and zigzag DWCNTs are around 2600 K-2700 K. At the pre-melting temperatures, the shrink of the dislocation loop, which is comprised of edge and screw dislocations, implies that the composite dislocation in DWCNTs has self-healing ability. The dislocated DWCNTs first fracture at the edge dislocations, which induces the entire break in axial tensile test. The dislocated DWCNTs have a smaller fracture strength compared to the perfect DWCNTs. Our results not only match with the dislocation glide of carbon nanotubes (CNTs) in experiments, but also can free from the electron beam radiation under experimental conditions observed by the high resolution transmission electron microscope (HRTEM), which is deemed to cause the motion of dislocation loop.
中图分类号: (Structure of carbon nanotubes, boron nanotubes, and other related systems)