Novel nanostructures suspended in graphene vacancies, edges and holes

Abstract

Under electron beam irradiation, graphene is inclined to form defects (such as vacancies and holes) that can trap foreign atoms to form new structures. The interactions between these structures and graphene have garnered considerable research interest as they can yield exciting properties. This review focuses on the fabrication and characterization of free-standing nanostructures suspended in graphene using transmission electron microscopy, which enables the observations with atomic resolution and investigations of the dynamic behavior of atoms/structures in such materials. Additionally, the review discusses the influence of novel metal/nonmetal dopants in graphene vacancies with varying bond configurations and the catalytic activities of single atoms/clusters located at the graphene edges. Moreover, the dynamic forming process of freestanding single-atom-thick two-dimensional (2D) clusters/metal/metallenes and 2D clusters/metal/metallenes oxides is discussed. Understanding the behavior, stabilities, and macroscopic effects of these nanostructures is vital for the practical deployment of novel atom/molecule scale nanotechnology. Overall, accumulative evidence confirms the growing number of these novel nanostructures, implying a bright future for further exciting discoveries.