Effects of Stone-Wales Defects on the Thermal Conductivity of Carbon Nanotubes

2012 ◽  
Vol 134 (9) ◽  
Author(s):  
Li Wei ◽  
Feng Yanhui ◽  
Peng Jia ◽  
Zhang Xinxin

The thermal conductivity of carbon nanotubes with Stone-Wales (SW) defects was investigated using non-equilibrium molecular dynamics method. The defect effects were analyzed by the temperature profile and local thermal resistance of the nanotubes with one or more SW defects and further compared with perfect tubes. The influences of the defect concentration, the length, the chirality and the radius of tubes and the ambient temperature were studied. It was demonstrated that a sharp jump in the temperature profile occurred at defect position due to a higher local thermal resistance, thus dramatically reducing the thermal conductivity of the nanotube. As the number of SW defects increases, the thermal conductivity decreases. Relative to the chirality, the radius has greater effects on the thermal conductivity of tubes with SW defects. With the similar radius, the thermal conductivity of armchair nanotube is higher than that of zigzag one. The shorter nanotube is more sensitive to the defect than the longer one. Thermal conductivity of the nanotube increases with ambient temperature, reaches a peak, and then decreases with increasing temperature.

Author(s):  
Arian Mayelifartash ◽  
Mohammad Ali Abdol ◽  
Sadegh Sadeghzadeh

In this paper, by employing non-equilibrium molecular dynamics simulations (NEMD), the thermal conductance of hybrid formed by polyaniline (C3N) and boron carbide (BC3) in both armchair and zigzag configurations has...


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Qiaoli Zhou ◽  
Fanyan Meng ◽  
Zhuhong Liu ◽  
Sanqiang Shi

The thermal conductivity of various carbon nanotubes with defects or intramolecular junctions was studied using nonequilibrium molecular dynamics approach. The results show that the thermal conductivity of both armchair and zigzag carbon nanotubes increased with the decrease of the radius of the tube. The thermal conductivity of armchair tube is higher than that of zigzag tube when the radii of the two tubes are kept almost same. Discontinuities appear on the temperature profile along the tube axial at the region of IMJ, resulting in the large temperature gradient and thus lower thermal conductivity of(n,n)/(m,0)tube with one IMJ and(m,0)/(n,n)/(m,0)tube with two IMJs. For the(m,0)/(n,n)/(m,0)tube with two IMJs, phonon mean free path of the middle(n,n)tube is much smaller than that of the isolate(n,n)tube.


2014 ◽  
Vol 1081 ◽  
pp. 338-342 ◽  
Author(s):  
Jing Hui Shi ◽  
Guang Yang ◽  
Xia Long Li ◽  
Xi Huang

Using classical non-equilibrium molecular dynamics simulations (NEMD), the interfacial thermal resistance and thermal rectification of nitrogen-doped zigzag graphene (NDZG) are investigated. Two different structural models about nitrogen-doped graphene are constructed. It is found that the interfacial thermal resistance at the location of nitrogen-doping causes severe reduction in thermal conductivity of the NDZG. Thermal rectification of the triangular single-nitrogen-doped graphene (SNDG) decreases with increasing temperature. However, thermal rectification is not detected in the parallel various–nitrogen-doped graphene (VNDG). These results suggest that SNDG might be a promising structure for thermal device.


2007 ◽  
Vol 1022 ◽  
Author(s):  
Junichiro Shiomi ◽  
Shigeo Maruyama

AbstractHeat conduction of finite-length single-walled carbon nanotubes (SWNTs) has been studied by means of non-equilibrium molecular dynamics (MD) simulations. The length-dependence of the thermal conductivity was quantified for a range of nanotube-lengths at room temperature. The length dependence of thermal conductivity exhibits a gradual transition from nearly pure ballistic heat conduction to diffusive-ballistic heat conduction. The results show that the thermal conductivity profile does not converge even beyond a micrometer nanotube-length. Furthermore, the diameter dependence suggests that the phonon diffusion is reduced with the diameter.


Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 809 ◽  
Author(s):  
Ravindra Sunil Dhumal ◽  
Dinesh Bommidi ◽  
Iman Salehinia

Variation in the thermal conductivity of a metal-coated tri-walled carbon nanotube (3WCNT), in the presence of vacancies, was studied using non-equilibrium molecular dynamics simulations. A Two-Temperature model was used to account for electronic contribution to heat transfer. For 3WCNT with 0.5% and 1% random vacancies, there was 76%, and 86% decrease in the thermal conductivity, respectively. In that order, an overall ~66% and ~140% increase in the thermal conductivity was recorded when 3 nm thick coating of metal (nickel) was deposited around the defective models. We have also explored the effects of tube specific and random vacancies on thermal conductivity of the 3WCNT. The changes in thermal conductivity have also been justified by the changes in vibrational density of states of the 3WCNT and the individual tubes. The results obtained can prove to be useful for countering the detrimental effects of vacancies in carbon nanotubes.


Author(s):  
Wei Li ◽  
Yanhui Feng ◽  
Jia Peng ◽  
Xinxin Zhang

Thermal conductivity of (5,5) and (3,3) carbon nanotubes with Stone-Wales (SW) defects is investigated by molecular dynamics simulation. Non-equilibrium molecular dynamics method is employed and the reactive empirical bond order potential is chosen. In the simulation, the temperature difference is given by applying the Berendsen thermostat model to each end of carbon nanotubes (CNTs). The thermal conductivity is calculated by Fourier’s equation. Different from linear temperature distribution along the tube for perfect CNTs without defects, there is temperature jump at defects for CNTs with a SW defect. The defect acts as additional phonon scattering centers and result in a local higher temperature gradient, which leads to a higher resistance to heat flow across the defect and thus a reduction in the thermal conductivity of the tube. The rotation angle of a SW defect barely influences the thermal conductivity of the tube. Probably, the thermal conductivity of CNTs with SW defects is more sensitive to the defect concentration than the defect distribution.


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