本文採用非平衡態分子動力學模擬方法，對一維奈米碳管及石墨烯奈米帶進行熱傳導率研究。在勢能函數採用REBO勢能(reactive empirical bond-order potential)及Tersoff勢能(Tersoff potential)描述原子間的作用力。對於熱傳導係數藉由Müller-Plathe提出的方法計算。在奈米尺度下，低溫時量子效應會影響熱傳導係數的正確性，必須加以修正。為了瞭解聲子導熱的基本機制，本文詳細的分析聲子態密度在不同情況下的變化。
研究首先分析(10，10)扶手椅型單壁奈米碳管，並指出空位缺陷的存在會降低熱傳導係數，而利用氮原子摻染於空位缺陷位置可改善熱傳導係數。此外，本文並研究不同幾何形狀及位置的氮摻染於奈米碳管的熱傳導係數。模擬結果指出奈米碳管會有非對稱性的熱輸運現象，這也就是熱整流現象，顯示出熱流在一個方向會優先輸運。而三角形分佈氮摻染所造成的非對稱性熱傳效果，遠比平行分佈氮摻染效果好。
最後，本文研究功能性石墨烯奈米帶吸附氫原子、甲基及苯基對熱傳導率的影響。當少量的氫原子隨機附著，降低熱傳導係數的程度大於氫原子叢聚附著。隨著附著率的增加，石墨烯奈米帶的熱傳導係數顯現陡降情形。此外，官能基使得原本碳原子的sp2鍵結轉變成sp3鍵結。模擬結果指出熱傳導率下降的主因為，較高的官能基平均角動量易於旋轉無固定的sp3鍵結，降低聲子的平均自由路徑。

The non-equilibrium molecular dynamics simulations are employed to investigate the thermal conductivity of one-dimensional carbon nanotubes (CNTs) and graphene nanoribbons (GNRs). The reactive empirical bond-order (REBO) potential and Tersoff potential are used to describe the interatomic interactions and the thermal conductivities are calculated using the Müller-Plathe approach. At the nanoscale, quantum effects influence the accuracy of the thermal conductivity at lower temperatures and should thus be corrected. In order to elucidate the underlying mechanism, we proceed with a detailed analysis of the phonon density of states under different systems.
First, the typical armchair (10, 10) single-walled CNTs is investigated. Vacancy defects decrease the thermal conductivity whereas the substitution of nitrogen at vacancy sites improves the thermal conductivity. Furthermore, the thermal conductivity of CNTs with geometric variations of doped nitrogen is investigated. The result is found that the CNTs has asymmetric axial thermal propagation; that is, the phenomenon of thermal rectification shows that the heat transfer is preferred in one direction. The triangular nitrogen-doped has more effect on the asymmetric heat transport than does parallel nitrogen-doped.
Finally, the thermal conductivity of GNRs functionalized by the chemical attachment of hydrogen、methyl and phenyl groups is investigated. A few hydrogen atoms randomly distributed reduces thermal conductivity more than that of cluster distribution. The GNRs exhibit a rapid drop in thermal conductivity with increasing degree of functionalization. In addition, functional group leads to conversion of carbon bonding from sp2 to sp3. The simulation results indicate that the rapid drop in thermal conductivity is a consequence of the higher angular momentum of functional groups, which rotate the unsupported sp3 bonds and thus reduce the phonon mean free paths.

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