Influence of Atomic Defect on the Deformation Properties of Nanowires Subjected to Uniaxial Tension

Atomic defects play an important role in the brittle deformation of nanowires at low temperatures. With molecular dynamics simulations, we study the influence of vacancy defects on the deformation and breaking behaviors of [10 oriented single-crystal gold nanowires at 50 and 150 K. The size of the nanowire is 10a × 10a × 30a (a stands for lattice constant, 0.408 nm for gold). It is shown that good crystalline structure appears in the whole deformation process, and it is in a brittle way at low temperature. The nanowire breaking behavior is sensitive to atomic vacancies when the atomic vacancy ratio is 1% in single-layer crystalline plane. Within the limitation of vacancy-induced breaking of the nanowire, the mechanical strengths increase under atomic vacancies. However, it decreases with the defect ratio increasing.

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Thermal conductivity of two-dimensional BC3: a comparative study with two-dimensional C3N

Physical Chemistry Chemical Physics ◽

10.1039/c9cp01943j ◽

2019 ◽

Vol 21 (24) ◽

pp. 12977-12985 ◽

Cited By ~ 8

Author(s):

Jieren Song ◽

Zhonghai Xu ◽

Xiaodong He ◽

Yujiao Bai ◽

Linlin Miao ◽

...

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Comparative Study ◽

Molecular Dynamics Simulations ◽

Environmental Temperature ◽

Single Layer ◽

Two Dimensional ◽

Vacancy Defects ◽

Dynamics Simulations ◽

External Strain

The thermal conductivities of single-layer BC3 (SLBC) sheets and their responses to environmental temperature, vacancy defects and external strain have been studied and compared with those of single-layer C3N (SLCN) sheets by molecular dynamics simulations.

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Schottky barrier tuning of the single-layer MoS2 on magnetic metal substrates through vacancy defects and hydrogenation

Physical Chemistry Chemical Physics ◽

10.1039/c6cp05384j ◽

2016 ◽

Vol 18 (45) ◽

pp. 31027-31032 ◽

Cited By ~ 3

Author(s):

Won Seok Yun ◽

J. D. Lee

Keyword(s):

Schottky Barrier ◽

Single Layer ◽

Metal Substrates ◽

Vacancy Defects ◽

Magnetic Metal ◽

Atomic Vacancy

The Schottky barrier and magnetism of the single-layer MoS2 on magnetic metal substrates can be tuned by atomic vacancy defects and hydrogenation.

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Uniaxial tension-induced fracture in gold nanowires with the dependence on size and atomic vacancies

Physical Chemistry Chemical Physics ◽

10.1039/c4cp03556a ◽

2014 ◽

Vol 16 (45) ◽

pp. 24716-24726 ◽

Cited By ~ 9

Author(s):

Fenying Wang ◽

Yanfeng Dai ◽

Jianwei Zhao ◽

Qianjin Li

Keyword(s):

Size Effect ◽

Uniaxial Tension ◽

Single Layer ◽

Gold Nanowires ◽

Crystalline Plane

The size effect dominates the rupture of gold nanowires, which is also related to atomic vacancies in a single-layer crystalline plane.

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Millisecond lattice gasification for high-density CO2- and O2-sieving nanopores in single-layer graphene

Science Advances ◽

10.1126/sciadv.abf0116 ◽

2021 ◽

Vol 7 (9) ◽

pp. eabf0116

Author(s):

Shiqi Huang ◽

Shaoxian Li ◽

Luis Francisco Villalobos ◽

Mostapha Dakhchoune ◽

Marina Micari ◽

...

Keyword(s):

Single Layer ◽

High Density ◽

Single Layer Graphene ◽

Pore Density ◽

Vacancy Defects ◽

Carbon Gasification ◽

Layer Graphene ◽

Gas Molecules ◽

Good Agreement

Etching single-layer graphene to incorporate a high pore density with sub-angstrom precision in molecular differentiation is critical to realize the promising high-flux separation of similar-sized gas molecules, e.g., CO2 from N2. However, rapid etching kinetics needed to achieve the high pore density is challenging to control for such precision. Here, we report a millisecond carbon gasification chemistry incorporating high density (>1012 cm−2) of functional oxygen clusters that then evolve in CO2-sieving vacancy defects under controlled and predictable gasification conditions. A statistical distribution of nanopore lattice isomers is observed, in good agreement with the theoretical solution to the isomer cataloging problem. The gasification technique is scalable, and a centimeter-scale membrane is demonstrated. Last, molecular cutoff could be adjusted by 0.1 Å by in situ expansion of the vacancy defects in an O2 atmosphere. Large CO2 and O2 permeances (>10,000 and 1000 GPU, respectively) are demonstrated accompanying attractive CO2/N2 and O2/N2 selectivities.

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Wedge Radius Effects in Mechanical Exfoliation of HOPG: A Molecular Simulation Study

Volume 1: Materials; Micro and Nano Technologies; Properties, Applications and Systems; Sustainable Manufacturing ◽

10.1115/msec2014-4168 ◽

2014 ◽

Cited By ~ 2

Author(s):

B. Jayasena ◽

S. Subbiah ◽

C. D. Reddy

Keyword(s):

Molecular Dynamics ◽

Pyrolytic Graphite ◽

Single Layer ◽

Layered Material ◽

Critical Depth ◽

Graphene Layers ◽

Highly Ordered Pyrolytic Graphite ◽

Single Sheet ◽

Dynamics Simulations ◽

Atomically Flat

We study the effects of wedge bluntness in mechanically exfoliating graphene layers from highly ordered pyrolytic graphite (HOPG), a layered material. Molecular dynamics simulations show that the layer initiation modes strongly depend on the wedge radius. Force and specific energy signatures are also markedly affected by the radius. Cleaving with a larger wedge radius causes buckling ahead of the wedge; larger the radius more the buckling. A critical depth of insertion of 1.6 A° is seen necessary to cleave a single layer; this is also found to be independent of wedge radius. Hence, with accurate positioning on an atomically flat HOPG surface it is possible to mechanically cleave, using a wedge, a single sheet of graphene even with a blunt wedge.

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Mechanical properties of boron nitride sheet with randomly distributed vacancy defects

Nanotechnology Reviews ◽

10.1515/ntrev-2019-0019 ◽

2019 ◽

Vol 8 (1) ◽

pp. 210-217 ◽

Cited By ~ 7

Author(s):

Yingjing Liang ◽

Hongfa Qin ◽

Jianzhang Huang ◽

Sha Huan ◽

David Hui

Keyword(s):

Mechanical Properties ◽

Boron Nitride ◽

Performance Optimization ◽

Fracture Strain ◽

Mechanical Performance ◽

Hexagonal Boron Nitride ◽

Stable Configuration ◽

Vacancy Defects ◽

And Performance ◽

Dynamics Simulations

Abstract Defects and temperature effects on the mechanical properties of hexagonal boron nitride sheet (h-BN) containing randomly distributed defects are investigated by molecular dynamics simulations and the reasons of the results are discussed. Results show that defect deteriorate the mechanical performance of BNNS. The mechanical properties are reduced by increasing percentage of vacancy defects including fracture strength, fracture strain and Young’s modulus. Simulations also indicate that the mechanical properties decrease with the temperature increasing. Moreover, defects affect the stable configuration at high temperature. With the percentage of defect increases the nanostructures become more and more unstable. Positions of the defect influent the mechanical properties. The higher the temperature and the percentage of defect are, the stronger the position of the randomly distributed defect affects the mechanical properties. The study provides a theoretical basis for the preparation and performance optimization of BNNSs.

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Molecular Dynamics Simulations of Deformation Behaviour of Gold Nanowires

Journal of Nanotechnology ◽

10.1155/2019/5710749 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

S. K. Joshi ◽

Kailash Pandey ◽

Sanjeev K. Singh ◽

Santosh Dubey

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Deformation Behaviour ◽

Electronic Devices ◽

Experimental Investigations ◽

Computational Techniques ◽

Gold Nanowires ◽

Classical Molecular Dynamics ◽

Au Nanowires ◽

Dynamics Simulations

Metallic nanowires show great potential for applications in miniaturization of electronic devices due to their extraordinary mechanical strength and electrical properties. Experimental investigations of these properties are difficult due to their size and complications in performing experiments at such length scales. Computational techniques based on classical molecular dynamics simulations (using LAMMPS) provide an effective mean to understand the mechanical deformation behaviour of such nanowires with considerable accuracy and predictability. In the present investigation, we have discussed the deformation behaviour of Au nanowires due to tensile loading using classical molecular dynamics simulations (LAMMPS). The effect of strain rate and temperature on the yield strength of the nanowire has been studied in detail. The deformation mechanisms have also been discussed.

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