EVALUATION OF FRACTURE AND FATIGUE PROPERTIES OF GRAPHENE OXIDE BY ATOMIC FORCE MICROSCOPE AND MOLECULAR DYNAMICS SIMULATION

Graphene is a typical two-dimensional material and is expected to be a next-generation material for structural and functional applications, including weight reduction and miniaturization of high-tech structures and devices. However, graphene is difficult to be synthesized in large quantities, and its practical application has not been well advanced because graphene is very sensitive to defects, and defects significantly decreases its strength and fatigue life. Therefore, we focused on graphene oxide (GO), in which functional groups such as hydroxy and epoxy groups are bonded to graphene. Since GO can be synthesized in large quantities and is endowed with ductile behavior, it is expected to be used in various applications such as supercapacitors and conductive high-strength composite materials. Since these devices are subjected to repeated loading and deformation in the process of use, it is very important to know the fracture and fatigue properties of GO. However, there are very few studies on the fracture and fatigue properties of GO. Therefore, this study evaluated the fracture and fatigue properties of GO using Atomic Force Microscope (AFM) experiments and molecular dynamics, and investigated the mechanisms of fracture and fatigue damage.