标题： 大尺度单晶石墨烯的力学行为 显示英文标题

标题： The Mechanical Behavior of Macroscale Single-crystal Graphene

摘要： 尽管已经开展了大量微尺度研究，单层石墨烯的宏观力学性能仍鲜有探索。在此，我们报告了厘米尺寸单晶单层石墨烯（SCG）“哑铃”形样品的杨氏模量（$E$ = 1.11 $\pm$ 0.04 太帕斯卡）、抗拉强度（${\sigma}$ = 27.40 $\pm$ 4.36 吉帕斯卡）以及失效应变（${\epsilon}_f$ = 6.01 $\pm$ 0.92 %），这些样品边缘沿锯齿形（zz）方向排列，并由超薄聚合物（聚碳酸酯）薄膜支撑。 对于边缘沿扶手椅（ac）方向的样品，我们得到 $E$ = 1.01 $\pm$ 0.10 TPa, ${\sigma}$ = 20.21 $\pm$ 3.22 GPa, ${\epsilon}_f$ = 3.69 $\pm$ 0.38 %；而对于边缘位于zz和ac之间的手性样品，我们得到 $E$= 0.75 $\pm$ 0.12 TPa, ${\sigma}$ = 23.56 $\pm$ 3.42 GPa，以及 ${\epsilon}_f$ = 4.53 $\pm$ 0.40 %。 通过化学气相沉积（CVD）法，将单晶Cu(111)箔片上的石墨烯单晶（SCG）生长出来。 我们使用了一种自制的“浮在水面上”（FOW）拉伸测试系统来进行拉伸载荷测量，并且该系统还能够实现裂纹的原位观测。 基于手性和缺口角度，定量断裂力学（QFM）分析预测边缘缺陷尺寸从几纳米到几十纳米不等。 通过韦伯分析，并考虑到致命缺陷局限于大尺度样品的边缘，根据它们的手性，我们预计A4尺寸的SCG强度范围从13.67到18.43 GPa。 大尺度单晶石墨烯（SCG）的卓越机械性能为其在各种广泛应用中的普及铺平了道路。 显示英文摘要

摘要： Despite extensive microscale studies, the macroscopic mechanical properties of monolayer graphene remain underexplored. Here, we report the Young's modulus ($E$ = 1.11 $\pm$ 0.04 TPa), tensile strength (${\sigma}$ = 27.40 $\pm$ 4.36 GPa), and failure strain (${\epsilon}_f$ = 6.01 $\pm$ 0.92 %) of centimeter-scale single-crystal monolayer graphene (SCG) 'dog bone' samples with edges aligned along the zigzag (zz) direction, supported by an ultra-thin polymer (polycarbonate) film. For samples with edges along the armchair (ac) direction, we obtain $E$ = 1.01 $\pm$ 0.10 TPa, ${\sigma}$ = 20.21 $\pm$ 3.22 GPa, ${\epsilon}_f$ = 3.69 $\pm$ 0.38 %, and for chiral samples whose edges were between zz and ac, we obtain $E$= 0.75 $\pm$ 0.12 TPa, ${\sigma}$ = 23.56 $\pm$ 3.42 GPa, and ${\epsilon}_f$ = 4.53 $\pm$ 0.40 %. The SCG is grown on single crystal Cu(111) foils by chemical vapor deposition (CVD). We used a home-built 'float-on-water' (FOW) tensile testing system for tensile loading measurements that also enabled in situ crack observation. The quantized fracture mechanics (QFM) analysis predicts an edge defect size from several to tens of nanometers based on chirality and notch angle. Through Weibull analysis and given that the fatal defects are confined on the edges of macroscale samples, we projected strength ranging from 13.67 to 18.43 GPa for an A4-size SCG according to their chirality. The exceptional mechanical performance of macroscale single crystal graphene (SCG) paves the way for its widespread use in a very wide variety of applications.