Graphene has huge application potential in the field of micro-nano devices, and due to the micro/nano-level application size, the thermal expansion coefficient of graphene has a certain impact on device performance. In this paper, a comprehensive study was carried out by molecular dynamics on the in-plane and through-plane thermal expansion effect of graphene. First of all, the in-plane thermal expansion coefficients of zigzag and armchair graphene were analyzed; they were similar and relatively close to the experiment value in the temperature range of 223–428 K. Secondly, the through-plane thermal expansion effect of double-layered graphene was investigated; the thermal expansion coefficient of through-plane was an order of magnitude larger than that of in-plane. Finally, the influence of graphene stacking on the thermal expansion effect was studied; Order-stacked graphene has a greater thermal expansion effect than that of AB- and ABC-stacked graphene. These discoveries in this article are of great significance to the development and application of graphene-based micro-nano devices.

石墨烯在微纳米器件领域具有巨大的应用潜力，由于微/纳米级的应用规模，石墨烯的热膨胀系数对器件性能有一定的影响。本文通过分子动力学对石墨烯的面内和面内热膨胀效应进行了全面研究。首先，分析了锯齿形和扶手椅形石墨烯的平面内热膨胀系数。它们在223-428 K的温度范围内相似且相对接近实验值。其次，研究了双层石墨烯的贯穿面热膨胀效应。平面内的热膨胀系数比平面内的热膨胀系数大一个数量级。最后，研究了石墨烯堆积对热膨胀效应的影响。有序堆叠的石墨烯比AB和ABC堆叠的石墨烯具有更大的热膨胀效应。本文中的这些发现对于基于石墨烯的微纳米器件的开发和应用具有重要意义。