Deciphering mechanical properties of 2D materials from the size distribution of exfoliated fragments

Two-dimensional (2D) materials have been attracting numerous research attention due to their distinctive physical properties and boundless application potential in various fields. Among diverse physical properties, the mechanical property is the most basic one and plays a crucial role in ensuring the high reliability of 2D material-based devices and products. However, characterizing the mechanical properties of 2D materials is always a challenge due to their atomic thickness. Here, we propose a facile method to decipher the mechanical property of 2D materials from the statistical distribution of the size of the fragments acquired via mechanical exfoliation. This method is essentially based on a probabilistic mechanics model correlating the distribution pattern of fragment size and the intrinsic mechanical properties of 2D materials. The ensuing experimental verifications on both graphene and 2H-MoS2 show good agreement between our measurements and the results reported in literature. This work not only provides a facile method for characterizing the mechanical properties of 2D materials, but also implies approaches to attaining 2D material fragments with controllable size via mechanical exfoliation. (C) 2019 Elsevier Ltd. All rights reserved.