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

Structure, stability, and motion of dislocations in double-wall carbon nanotubes

张凯旺, 李中秋, 吴建, 彭向阳, 谭新君, 孙立忠, 钟建新   

  1. Laboratory for Quantum Engineering and Micro-Nano Energy Technology and Department of Physics, Xiangtan University, Xiangtan 411105, China
  • 收稿日期:2012-03-09 修回日期:2012-04-17 出版日期:2012-09-01 发布日期:2012-09-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10974166 and 10774127), the Cultivation Fund of the Key Scientific and Technical Innovation Project of the Ministry of Education of China (Grant No. 708068), and the Research Foundation of Education Bureau of Hunan Province, China (Grant Nos. 09A094 and 10A118).

Structure, stability, and motion of dislocations in double-wall carbon nanotubes

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)   

  1. Laboratory for Quantum Engineering and Micro-Nano Energy Technology and Department of Physics, Xiangtan University, Xiangtan 411105, China
  • Received:2012-03-09 Revised:2012-04-17 Online:2012-09-01 Published:2012-09-01
  • Contact: Zhang Kai-Wang E-mail:kwzhang@xtu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10974166 and 10774127), the Cultivation Fund of the Key Scientific and Technical Innovation Project of the Ministry of Education of China (Grant No. 708068), and the Research Foundation of Education Bureau of Hunan Province, China (Grant Nos. 09A094 and 10A118).

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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.

关键词: dislocation, carbon nanotube, molecular dynamics, thermal stability

Abstract: 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.

Key words: dislocation, carbon nanotube, molecular dynamics, thermal stability

中图分类号:  (Structure of carbon nanotubes, boron nanotubes, and other related systems)

  • 61.48.De
61.72.Cc (Kinetics of defect formation and annealing) 71.15.Pd (Molecular dynamics calculations (Car-Parrinello) and other numerical simulations)