scholarly journals Extracting the inner wall from nested double-walled carbon nanotube by platinum nanowire: molecular dynamics simulations

RSC Advances ◽  
2017 ◽  
Vol 7 (63) ◽  
pp. 39480-39489 ◽  
Author(s):  
Dan Xia ◽  
Yongchao Luo ◽  
Qiang Li ◽  
Qingzhong Xue ◽  
Xiaomin Zhang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Carbon Nanotube ◽  
Molecular Dynamics Simulations ◽  
Multi Walled Carbon Nanotubes ◽  
Dynamics Simulations ◽  
Walled Carbon Nanotubes

The Pt nanowire with proper diameter is able to extract the inner wall/s in nested double-walled/multi-walled carbon nanotubes. For the multi-walled carbon nanotubes, the Pt nanowire with proper diameter can only peel off the outermost wall.

The Unravelling of Open-Ended Single Walled Carbon Nanotubes Using Molecular Dynamics Simulations

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
Tarek Ragab ◽  
Cemal Basaran
Keyword(s):  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Carbon Nanotube ◽  
Molecular Dynamics Simulations ◽  
Single Walled Carbon Nanotubes ◽  
Atomic Chain ◽  
Single Walled Carbon ◽  
Different Temperatures ◽  
Dynamics Simulations ◽  
Walled Carbon Nanotubes

The unravelling of (10, 10) and (18, 0) single-walled carbon nanotubes (SWCNTs) is simulated using molecular dynamics simulations at different temperatures. Two different schemes are proposed to simulate the unravelling; completely restraining the last atom in the chain and only restraining it in the axial direction. The forces on the terminal atom in the unravelled chain in the axial and radial directions are reported till the separation of the atomic chain from the carbon nanotube structure. The force-displacement relation for a chain structure at different temperatures is calculated and is compared to the unravelling forces. The axial stresses in the body of the carbon nanotube are calculated and are compared to the failure stresses of that specific nanotube. Results show that the scheme used to unravel the nanotube and the temperature can only effect the duration needed before the separation of some or all of the atomic chain from the nanotube, but does not affect the unravelling forces. The separation of the atomic chain from the nanotube is mainly due to the impulsive excessive stresses in the chain due to the addition of a new atom and rarely due to the steady stresses in the chain. From the simulations, it is clear that the separation of the chain will eventually happen due to the closing structure occurring at the end of the nanotube that would not be possible in multiwalled nanotubes.

Molecular Dynamics Study on Thermal Conductivity of Single-Walled Carbon Nanotubes

2009 ◽  
Author(s):  
Bingyang Cao ◽  
Quanwen Hou ◽  
Zengyuan Guo ◽  
Wusheng Zhang
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Carbon Nanotube ◽  
Molecular Dynamics Simulations ◽  
Phonon Transport ◽  
Tube Length ◽  
Length Dependence ◽  
Dynamics Simulations ◽  
Walled Carbon Nanotubes

In this paper, we study the thermal conductivities of sing-walled carbon nanotubes (CNTs) and CNTs-based nanocomposites using molecular dynamics simulations. Length dependence of the thermal conductivity of (5, 5) carbon nanotube at 300 K and 1000 K is simulated. At room temperature the thermal conductivity shows linear length dependence with the tube length less than 40 nm, which indicates the completely ballistic transport. The thermal conductivity increases with the increase of the nanotube length, but the increase rate decreases as the length increases. It shows that the phonon transport transits from ballistic to diffusive. In the simulations, the power exponent of the thermal conductivity of carbon nanotube to the tube length decreases by decaying exponential function as the tube length increases. We also observe a decrease of the low-dimensional effects by the surrounding matters. A carbon-nanotube-atom-fixed and -activated scheme of non-equilibrium molecular dynamics simulations is put forward to extract the thermal conductivity of carbon nanotubes embedded in solid argon. Though a 6.5% volume fraction of CNTs increases the composite thermal conductivity by about twice larger than that of the pure basal material, the thermal conductivity of CNTs embedded in solids is found to be decreased by 1/8–1/5 with reference to that of pure ones. The decrease of the intrinsic thermal conductivity of the solid-embedded CNTs and the thermal interface resistance are demonstrated to be responsible for the results.

scholarly journals Molecular Dynamics Simulations and Theoretical Model for Engineering Tensile Properties of Single-and Multi-Walled Carbon Nanotubes

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 795
Author(s):  
Keiichi Shirasu ◽  
Shunsuke Kitayama ◽  
Fan Liu ◽  
Go Yamamoto ◽  
Toshiyuki Hashida
Keyword(s):  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Number Of Layers ◽  
Effective Strength ◽  
Nominal Strength ◽  
Multi Walled Carbon Nanotubes ◽  
Dynamics Simulations ◽  
Walled Carbon Nanotubes ◽  
Walled Cnts

To apply carbon nanotubes (CNTs) as reinforcing agents in next-generation composites, it is essential to improve their nominal strength. However, since it is difficult to completely remove the defects, the synthesis guideline for improving nominal strength is still unclear, i.e., the effective strength and the number of nanotube layers required to improve the nominal strength has been undermined. In this study, molecular dynamics simulations were used to elucidate the effects of vacancies on the mechanical properties of CNTs. Additionally, the relationships between the number of layers and effective and nominal strengths of CNTs were discussed theoretically. The presence of extensive vacancies provides a possible explanation for the low nominal strengths obtained in previous experimental measurements of CNTs. This study indicates that the nominal strength can be increased from the experimentally obtained values of 10 GPa to approximately 20 GPa by using six to nine nanotube layers, even if the increase in effective strength of each layer is small. This has advantages over double-walled CNTs, because the effective strength of such CNTs must be approximately 60 GPa to achieve a nominal strength of 20 GPa.

scholarly journals A NOVEL DESIGN OF PERISTALTIC CARBON NANO PUMP AND AN ANALYSIS OF HELIUM FLOW

2021 ◽  
Vol 55 (6) ◽  
Author(s):  
M. Gokhan Günay ◽  
Ubade Kemerli
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Pump Design ◽  
Helium Atoms ◽  
Multi Walled Carbon Nanotubes ◽  
Temperature And Pressure ◽  
Dynamics Simulations ◽  
Walled Carbon Nanotubes ◽  
Novel Design ◽  
Main Carbon

A novel nano-scale pump that can transport atoms or small molecules with a peristaltic motion is designed. It is proven by molecular-dynamics simulations that the introduced nano-pump design works properly. The designed nano-pump consists of one main carbon nanotube named the flow tube and two rotors where multi-walled carbon nanotubes are attached. The pumping of helium atoms by the designed peristaltic carbon nano-pump is investigated by molecular-dynamics simulations. For varying rotor speeds and blade counts, time-averaged velocity, temperature, and pressure results of pumped helium atoms are calculated, and relationships between them are modeled as polynomial surfaces. The results showed that rotor frequency increases the velocity of helium linearly and the temperature and pressure of helium non-linearly. Furthermore, the blade count of the proposed mechanism does not substantially affect the velocity as per the previous studies in the literature.

Sign in / Sign up

Export Citation Format

Share Document