Buckling Behavior of Few-Layer Graphene on Soft Substrate

The buckling behavior of graphene on soft films has been extensively studied. However, to avoid graphene fracture, most studies focus only on the primary buckling behavior induced by tiny compression. Here, the buckling behavior of monolayer, three-layer, and four-layer graphene on soft films is systematically studied in the experiment under large compression. The cross-sections of buckling patterns in these few-layer graphenes are provided, which depend on focused ion beam (FIB) technology. More significantly, the moduli of few-layer graphene are calculated based on the buckling behavior. We demonstrate that the modulus, 1.12621 TPa, is independent of the number of graphene layers if the number is less than four. Our investigations are crucial for the application of two-dimensional (2D) materials into flexible hybrid electronics, bionics, and various other stiff/soft bilayer systems.