Hierarchical structure and properties of graphene oxide papers

The mechanical properties of graphene oxide papers have attracted significant attention in recent years due to their high stiffness and tough behavior. While the structural feature most commonly characterized is the nanosheet spacing, there is a hierarchical structure, which is likely responsible for the impressive mechanical properties. In this paper, we examine the structure of graphene oxide papers on several length scales using novel techniques to distinguish between lamellae and a newly defined feature, termed "super-lamellae." The differentiation between these intermediate features provides context to the previously observed mechanical response and fracture surfaces of graphene oxide papers, particularly under uniaxial tension.