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Defect-related hysteresis in nanotube-based nano-electromechanical systems.

Tsetseris L, Pantelides ST - Nanoscale Res Lett (2011)

Bottom Line: This fact can enable several applications of MWCNTs as nano-electromechanical systems (NEMS).Key defect-related effects, namely, sudden energy changes and hysteresis, are identified, and their relevance to a host of MWCNT-based NEMS is highlighted.The results also demonstrate the dependence of these effects on defect clustering and chirality of DWCNT shells.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physics, National Technical University of Athens, GR-15780 Athens, Greece. leont@mail.ntua.gr.

ABSTRACT
The electronic properties of multi-walled carbon nanotubes (MWCNTs) depend on the positions of their walls with respect to neighboring shells. This fact can enable several applications of MWCNTs as nano-electromechanical systems (NEMS). In this article, we report the findings of a first-principles study on the stability and dynamics of point defects in double-walled carbon nanotubes (DWCNTs) and their role in the response of the host systems under inter-tube displacement. Key defect-related effects, namely, sudden energy changes and hysteresis, are identified, and their relevance to a host of MWCNT-based NEMS is highlighted. The results also demonstrate the dependence of these effects on defect clustering and chirality of DWCNT shells.

No MeSH data available.


Related in: MedlinePlus

Pairs of carbon interstitials in a (9,0)@(18,0) double-wall carbon nanotube. (a) Inter-tube bridge (arrows point to C interstitials), (b) hillock on the inner (9,0) tube (the atoms and bonds of the outer shell are shown in a wire frame).
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Figure 2: Pairs of carbon interstitials in a (9,0)@(18,0) double-wall carbon nanotube. (a) Inter-tube bridge (arrows point to C interstitials), (b) hillock on the inner (9,0) tube (the atoms and bonds of the outer shell are shown in a wire frame).

Mentions: Given that SI defects tend to agglomerate on graphene and SWCNT [4,5], it is natural to probe whether similar trends appear for defects in DWCNTs. Indeed, pairs of SIs in a (9,0)@(18,0) DWCNT have significant binding energy against dissociation to individual defects. The most stable pair structure is shown in Figure 2b. It has a binding energy of 5.4 eV, and it resembles the hillock SI defect found on graphene and SWCNTs [4]. A large binding energy and a SI diffusion barrier of 1.6 eV suggest that the stable hillock is formed under annealing at moderate temperature above room conditions.


Defect-related hysteresis in nanotube-based nano-electromechanical systems.

Tsetseris L, Pantelides ST - Nanoscale Res Lett (2011)

Pairs of carbon interstitials in a (9,0)@(18,0) double-wall carbon nanotube. (a) Inter-tube bridge (arrows point to C interstitials), (b) hillock on the inner (9,0) tube (the atoms and bonds of the outer shell are shown in a wire frame).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211306&req=5

Figure 2: Pairs of carbon interstitials in a (9,0)@(18,0) double-wall carbon nanotube. (a) Inter-tube bridge (arrows point to C interstitials), (b) hillock on the inner (9,0) tube (the atoms and bonds of the outer shell are shown in a wire frame).
Mentions: Given that SI defects tend to agglomerate on graphene and SWCNT [4,5], it is natural to probe whether similar trends appear for defects in DWCNTs. Indeed, pairs of SIs in a (9,0)@(18,0) DWCNT have significant binding energy against dissociation to individual defects. The most stable pair structure is shown in Figure 2b. It has a binding energy of 5.4 eV, and it resembles the hillock SI defect found on graphene and SWCNTs [4]. A large binding energy and a SI diffusion barrier of 1.6 eV suggest that the stable hillock is formed under annealing at moderate temperature above room conditions.

Bottom Line: This fact can enable several applications of MWCNTs as nano-electromechanical systems (NEMS).Key defect-related effects, namely, sudden energy changes and hysteresis, are identified, and their relevance to a host of MWCNT-based NEMS is highlighted.The results also demonstrate the dependence of these effects on defect clustering and chirality of DWCNT shells.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physics, National Technical University of Athens, GR-15780 Athens, Greece. leont@mail.ntua.gr.

ABSTRACT
The electronic properties of multi-walled carbon nanotubes (MWCNTs) depend on the positions of their walls with respect to neighboring shells. This fact can enable several applications of MWCNTs as nano-electromechanical systems (NEMS). In this article, we report the findings of a first-principles study on the stability and dynamics of point defects in double-walled carbon nanotubes (DWCNTs) and their role in the response of the host systems under inter-tube displacement. Key defect-related effects, namely, sudden energy changes and hysteresis, are identified, and their relevance to a host of MWCNT-based NEMS is highlighted. The results also demonstrate the dependence of these effects on defect clustering and chirality of DWCNT shells.

No MeSH data available.


Related in: MedlinePlus