Abstract

Since the success of monolayer graphene exfoliation, two-dimensional (2D) materials have been extensively studied due to their unique structures and unprecedented properties. Among these fascinating studies, the most predominant focus has been on their atomic structures, defects, and mechanical behaviors and properties, which serve as the basis for the practical applications of 2D materials. In this review, we first highlight the atomic structures of various 2D materials and the structural and energy features of some common defects. We then summarize the recent advances made in experimental, computational, and theoretical studies on the mechanical properties and behaviors of 2D materials. We mainly emphasized the underlying deformation and fracture mechanisms and the influences of various defects on mechanical behaviors and properties, which boost the emergence and development of topological design and defect engineering. We also further introduce the piezoelectric and flexoelectric behaviors of specific 2D materials to address the coupling between mechanical and electronic properties in 2D materials and the interactions between 2D crystals and substrates or between different 2D monolayers in heterostructures. Finally, we provide a perspective and outlook for future studies on the mechanical behaviors and properties of 2D materials.

Highlights

  • We review the recent advances in the intrinsic microstructures and unique mechanics of 2D materials to provide a fundamental understanding of their mechanical behaviors and properties

  • We summarize recent advances in experimental, computational, and theoretical studies on the mechanical behaviors and properties of various 2D materials, including their tension and fracture behaviors, piezoelectricity, flexoelectricity, friction, interlayer shear properties, and van der Waals interactions

  • We further emphasize that some common defects in 2D materials have a profound influence on their mechanical behaviors, suggesting tunable properties by defect engineering

Read more

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Have been extracted at an early stage and have recently received much attention Some graphene analogs such as black phosphorene [39], borophene [40,41], silicene [42,43], germanane [44], stanene [45], antimonene [46], bismuthene [47,48] and tellurene [49] have been synthesized in the past few years. These 2D materials have an atomic layer structure similar to that of graphene, their physical properties are distinct from those of graphene. We provide a perspective and outlook for future studies on the mechanical behaviors and properties of 2D materials

Classification and Atomic Structures
Structural Defects in Various 2D Materials
Point Defects
Dislocations and Grain Boundaries
Experimental Measurements via Nanoindentation in Atomic Force Microscopy
First-Principle Calculations and MD Simulations
Theoretical Modeling
Grain Size Effect on the Strength of Polycrystalline Graphene
Model I Fracture of 2D Materials
Toughening Mechanisms
Other Fracture Modes
Fatigue Failure
Piezoelectricity and Flexoelectricity
Sliding Friction on Surfaces
Friction Modulation
Van der Waals Interaction between 2D Materials and Substrate
Tunable Band Gap of 2D Materials on a Substrate
Van der Waals Interface of Heterostructures
Conclusions and Perspectives
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call