Center for Mechanics of Solids, Structures and Materials, Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712, USA.
CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology, Beijing 100190, China.
Phys Rev Lett. 2018 Dec 28;121(26):266101. doi: 10.1103/PhysRevLett.121.266101.
Nanoblisters such as nanobubbles and nanotents formed by two-dimensional (2D) materials have been extensively exploited for strain engineering purposes as they can produce self-sustained, nonuniform in-plane strains through out-of-plane deformation. However, deterministic measure and control of strain fields in these systems are challenging because of the atomic thinness and unconventional interface behaviors of 2D materials. Here, we experimentally characterize a simple and unified power law for the profiles of a variety of nanobubbles and nanotents formed by 2D materials such as graphene and MoS_{2} layers. Using membrane theory, we analytically unveil what sets the in-plane strains of these blisters regarding their shape and interface characteristics. Our analytical solutions are validated by Raman spectroscopy measured strain distributions in bulged graphene bubbles supported by strong and weak shear interfaces. We advocate that both the strain magnitudes and distributions can be tuned by 2D material-substrate interface adhesion and friction properties.
纳米气泡囊，如由二维（2D）材料形成的纳米气泡和纳米帐篷，已被广泛用于应变工程，因为它们可以通过面外变形产生自维持的、非均匀的面内应变。然而，由于 2D 材料的原子级薄度和非常规的界面行为，这些系统中应变场的确定性测量和控制具有挑战性。在这里，我们通过实验对由二维材料（如石墨烯和 MoS_{2}层）形成的各种纳米气泡囊和纳米帐篷的轮廓进行了简单而统一的幂律特性进行了描述。我们使用膜理论，从形状和界面特征方面解析了这些气泡囊的面内应变的影响因素。我们的分析解通过在强和弱剪切界面支撑下的膨胀石墨烯气泡的拉曼光谱测量应变分布进行了验证。我们主张通过 2D 材料-基底界面附着力和摩擦特性可以调节应变幅度和分布。
