Graphene, which is one of the most promising materials for its state-of-the-art applications, has received extensive attention because of its superior mechanical properties. However, there is little experimental evidence related to the mechanical properties of graphene at the atomic level because of the challenges associated with transferring atomically-thin two-dimensional (2D) materials onto microelectromechanical systems (MEMS) devices. In this study, we show successful dry transfer with a gel material of a stable, clean, and free-standing exfoliated graphene film onto a push-to-pull (PTP) device, which is a MEMS device used for uniaxial tensile testing in in situ transmission electron microscopy (TEM). Through the results of optical microscopy, Raman spectroscopy, and TEM, we demonstrate high quality exfoliated graphene on the PTP device. Finally, the stress–strain results corresponding to propagating cracks in folded graphene were simultaneously obtained during the tensile tests in TEM. The zigzag and armchair edges of graphene confirmed that the fracture occurred in association with the hexagonal lattice structure of graphene while the tensile testing. In the wake of the results, we envision the dedicated preparation and in situ TEM tensile experiments advance the understanding of the relationship between the mechanical properties and structural characteristics of 2D materials.

中文翻译：

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剥离石墨烯原位透射电子显微镜拉伸测试专用制剂

石墨烯是最有前途的应用材料之一，因其优异的机械性能而受到广泛关注。然而，由于将原子级薄的二维 (2D) 材料转移到微机电系统 (MEMS) 设备上存在挑战，因此几乎没有与石墨烯在原子水平上的机械性能相关的实验证据。在这项研究中，我们展示了使用稳定、清洁和独立的剥离石墨烯膜的凝胶材料成功干转移到推拉 (PTP) 设备上，这是一种用于单轴拉伸测试的 MEMS 设备原位透射电子显微镜（TEM）。通过光学显微镜、拉曼光谱和 TEM 的结果，我们在 PTP 设备上展示了高质量的剥离石墨烯。最后，在 TEM 拉伸试验期间，同时获得了与折叠石墨烯中裂纹扩展对应的应力应变结果。石墨烯的锯齿形和扶手椅边缘证实，在拉伸测试时，断裂与石墨烯的六方晶格结构有关。根据结果​​，我们设想专用的制备和原位 TEM 拉伸实验促进对 2D 材料的机械性能和结构特征之间关系的理解。石墨烯的锯齿形和扶手椅边缘证实，在拉伸测试时，断裂与石墨烯的六方晶格结构有关。根据结果​​，我们设想专用的制备和原位 TEM 拉伸实验促进对 2D 材料的机械性能和结构特征之间关系的理解。石墨烯的锯齿形和扶手椅边缘证实，在拉伸测试时，断裂与石墨烯的六方晶格结构有关。根据结果​​，我们设想专用的制备和原位 TEM 拉伸实验促进对 2D 材料的机械性能和结构特征之间关系的理解。