Designing the Bending Stiffness of 2D Material Heterostructures

2D monolayers represent some of the most deformable inorganic materials, with bending stiffnesses approaching those of lipid bilayers. Achieving 2D heterostructures with similar properties would enable a new class of deformable devices orders of magnitude softer than conventional thin‐film electronics. Here, by systematically introducing low‐friction twisted or heterointerfaces, interfacial engineering is leveraged to tailor the bending stiffness of 2D heterostructures over several hundred percent. A bending model is developed and experimentally validated to predict and design the deformability of 2D heterostructures and how it evolves with the composition of the stack, the atomic arrangements at the interfaces, and the geometry of the structure. Notably, when each atomic layer is separated by heterointerfaces, the total bending stiffness reaches a theoretical minimum, equal to the sum of the constituent layers regardless of scale of deformation—lending the extreme deformability of 2D monolayers to device‐compatible multilayers. Interfacial engineering is used to tune the bending stiffness of 2D material heterostructures composed of graphene and MoS2 by over several hundred percent. The incorporation of twisted or heterointerfaces facilitates interlayer slip, which dramatically softens the 2D stacks. A bending model is developed to predict and design the deformability of 2D heterostructures as a function of composition, stacking order, and geometry of the structure.