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arXiv · 1007.4406

Self-repairing in single-walled carbon nanotubes by heat treatment

Jin-Wu Jiang·Jian-Sheng Wang
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Abstract

Structure transformation by heat treatment in single-walled carbon nanotubes (SWCNT) is investigated using molecular dynamics simulation. The critical temperature for the collapse of pure SWCNT is as high as 4655 K due to strong covalent carbon-carbon bonding. Above 2000 K, the cross section of SWCNT changes from circle to ellipse. The self-repairing capability is then investigated and two efficient processes are observed for the SWCNT to repair themselves. (1) In the first mechanism, vacancy defects aggregate to form a bigger hole, and a bottleneck junction is constructed nearby. (2) In the second mechanism, a local curvature is generated around the isolate vacancy to smooth the SWCNT. Benefit from the powerful self-repairing capability, defective SWCNT can seek a stable configuration at high temperatures; thus the critical temperature for collapse is insensitive to the vacancy defect density.

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Jin-Wu Jiang, Jian-Sheng Wang. 2010-07-26. Self-repairing in single-walled carbon nanotubes by heat treatment. https://doi.org/10.1063/1.3481004

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