The 2D form of diamond with a bilayer sp3 carbon nanostructure has been theoretically predicted in 2009, while its experimental synthesis has only been reported very recently after 2017 [1-3]. Many names have been used for nanometer-thick diamond films, such as diamane, diamondol, lonsdaleitene, diamondene, and diamene. For general referencing purpose, we name these new nanometer-thick diamond as 2D diamane. The enthusiastic about 2D diamane is partly powdered by the rapid development of 2D nanostructures, another major driver is the excellent properties of diamond that make them ideal for new-generation high-power electronic devices, especially under extreme conditions.

Bending is a common deformation scenario for flexible electronics. Though there are many works examined the bending properties of 2D nanomaterials [4], very few have discussed their bending limit. Based on molecular dynamic simulations, this work systemically investigated the bending limit of 2D diamane. According to the three-point bending simulation, 2D diamane exhibits a strong nonlinear bending behavior, which is originated from the axial extension effect. More interestingly, the critical tensile strain when the 2D diamane experience fracture as induced by bending is different from that under pure tensile deformation. Examining the atomic configurations, different fracture mechanisms are observed under bending and tensile deformation, suggesting that the bending limit of 2D diamane can’t be described by the classical theory.