由於現代電子零件需要在有限的晶片內集成更多的功能，會產生更多的熱量。因此，散熱能力成為了一個重要的課題。石墨烯是一種輕薄、強韌、高導電、高導熱的材料，其單層厚度約為0.345納米。由於石墨烯原子之間的鍵結穩定且非常強，所以它具有極高的機械強度，甚至比鋼鐵還要堅韌，可以承受高強度的拉伸，拉伸性能也超越了許多金屬，石墨烯還具有優異的導電性和導熱性，甚至超越了傳統金屬銀。是非常特殊的材料，可解決現代電子設備中面臨的導熱問題。
本研究通過LAMMPS分子動力學進行模擬，條件建立在傅立葉定律和Green-Kubo公式，計算石墨烯的熱傳導係數，以及尺度、溫度、空位缺陷、同位素摻雜效應對其熱傳導係數的影響，吾人還透過將速度自相關函數進行傅立葉轉換，直接觀察熱傳下聲子的傳輸行為，並畫出聲子狀態密度圖，瞭解上述效應影響熱傳導係數的原因，並做深入的研究，這將有助於深入研究石墨烯的熱傳機制。
研究發現單層石墨烯的熱傳導係數嚴重受到缺陷率的影響，下降幅到高達驚人的94%，缺陷率增大對熱傳導係數具有顯著的降低作用。隨著石墨烯層數增加到六層，其熱傳導係數下降約57%，而在旋轉石墨烯中，層間扭轉角度的改變也對熱傳導係數造成了下降四成左右的影響。多層石墨烯進行實際應用時，其熱傳導性能將不如單層石墨烯。在多層旋轉石墨烯的旋轉效應下，只有在無旋轉的情況下才能獲得最高的熱導率。儘管目前單層無缺陷石墨烯的科技應用仍然有待發展，但它已成為了未來科技發展的一個熱門研究領域。

Modern electronic components require more functions within limited chip space, making heat dissipation crucial. Graphene, a lightweight, thin, strong, highly electrically conductive material with a thickness of only 0.345 nanometers. It also offers excellent thermal conductivity and promises to solve heat dissipation problems in modern electronic devices.
In this study, we employed LAMMPS molecular dynamics simulations to calculate graphene's thermal conductivity based on Fourier's law and the Green-Kubo formula. We investigated the effects of scale, temperature, vacancy defects, and isotope doping on the thermal conductivity coefficient. We also used the velocity autocorrelation function for Fourier transformation to observe phonon transport behavior under heat conduction. We generated a phonon density of states plot, providing an in-depth analysis of the factors influencing the thermal conductivity coefficient.
Research revealed that the thermal conductivity coefficient of monolayer graphene was significantly affected by defect density, leading to a decrease of up to 94%. As defect density increased, the thermal conductivity coefficient decreased. When the number of graphene layers increased to six, the thermal conductivity coefficient decreased by approximately 57%. In rotated graphene, changes in interlayer twist angles also resulted in a reduction of the thermal conductivity coefficient by about 40%. In practical applications, multilayer graphene exhibited lower thermal conductivity performance than monolayer graphene. In multilayer rotated graphene, the highest thermal conductivity could only be achieved without a twist angle. Although defect-free monolayer graphene was still under development, it became a hot research area for future technology advancements.

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