Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai Institute of Aircraft Mechanics and Control, Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Frontier Science Center of Mechanoinformatics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, People's Republic of China.
Zhejiang Laboratory, Hangzhou 311100, China.
Phys Chem Chem Phys. 2023 Mar 15;25(11):7734-7740. doi: 10.1039/d2cp04638e.
Single-walled carbon nanotubes (SWCNTs) possess extremely high thermal conductivity that benefits their application in high-performance electronic devices. The characteristic hollow configuration of SWCNTs is not favorable for the buckling stability of the structure, which is typically resolved by fullerene encapsulation in practice. To investigate the fullerene encapsulation effect on thermal conductivity, we perform molecular dynamics simulations to comparatively study the thermal conductivity of pure SWCNTs and fullerene encapsulated SWCNTs. We focus on disclosing the relationship between the vacancy defect and the fullerene encapsulation effect on thermal conductivity. It is quite interesting that vacancy defects weaken the coupling strength between the nanotube shell and the fullerene, especially for narrower SWCNTs (9, 9), which will considerably reduce the effect of fullerene encapsulation on the thermal conductivity of narrower SWCNTs. However, for thicker SWCNTs (10, 10) and (11, 11), vacancy defects have an ignorable effect on the coupling strength between the nanotube shell and the fullerene due to plenty of free space in thicker SWCNTs, so vacancy defects are not important for the fullerene encapsulation effect on the thermal conductivity of thicker SWCNTs. These findings shall be valuable for the application of SWCNTs in thermoelectric fields.
单壁碳纳米管（SWCNTs）具有极高的热导率，这使其在高性能电子设备中的应用受益。SWCNTs 的独特空心结构不利于结构的屈曲稳定性，这在实践中通常通过富勒烯封装来解决。为了研究富勒烯封装对热导率的影响，我们进行了分子动力学模拟，比较研究了纯 SWCNTs 和富勒烯封装的 SWCNTs 的热导率。我们专注于揭示空位缺陷与富勒烯封装对热导率的影响之间的关系。有趣的是，空位缺陷削弱了纳米管壳与富勒烯之间的耦合强度，特别是对于更窄的 SWCNTs（9,9），这将大大降低富勒烯封装对更窄 SWCNTs 热导率的影响。然而，对于较厚的 SWCNTs（10,10）和（11,11），由于较厚的 SWCNTs 中有大量的自由空间，空位缺陷对纳米管壳与富勒烯之间的耦合强度的影响可以忽略不计，因此空位缺陷对于富勒烯封装对较厚 SWCNTs 的热导率的影响并不重要。这些发现对于 SWCNTs 在热电领域的应用具有重要价值。
