▎ 摘　　要

The peeling and sliding behaviors of graphene nanoribbons (GNRs) atop a graphene substrate are studied by a continuum model and numerical simulations. A periodic potential energy function is used to simulate the van der Waals interactions between the GNRs and the substrate in both the normal and tangential directions, coupling adhesion and friction within the same model. Numerical simulations and associated analyses reveal remarkably rich dynamics in peeling and sliding of GNRs. It is found that the simple 90-degree peeling of a GNR depends primarily on the normal (adhesive) interactions, with negligible sliding or shear interactions. In contrast, peeling with the end fixed in the in-plane directions leads to stick-slip sliding, with a higher peeling force and a critical peeling angle depending on both adhesion and friction. Notably, the stick-slip sliding is facilitated by formation and gliding of strain solitons in GNRs, and different types of strain solitons may form in the zigzag, armchair and chiral GNRs, including tensile, shear and mixed types. Unconstrained sliding is typically accompanied by both lateral and normal displacements, while constraining the displacements in the normal or lateral directions would generally lead to a higher pulling force for sliding. The peak pulling force as a measure of the sliding friction depends on the ribbon width quasi-linearly but becomes nearly independent of the ribbon length for relatively long GNRs (L >20 nm). Finally, two cases with coupled peeling and sliding of GNRs are considered, and a simple analysis is proposed to simultaneously determine the adhesion and friction properties of GNRs from measurable quantities in potential experiments.