Adhesion Mechanics of Two-Dimensional Materials

Two-dimensional (2D) materials such as graphene, hexagonal boron nitride and transition-metal dichalcogenides exhibit unique adhesion mechanics arising from their atomically thin geometry and strong in-plane bonding coupled with weak out-of-plane interactions. At the heart of this behaviour lies the balance between van der Waals attraction, which governs interlayer adhesion and adhesion to substrates, and the elastic energy required to deform an ultrathin membrane. Precise measurement and control of adhesion energy underpin the fabrication of heterostructures, the stability of nanoscale bubbles and the performance of micro- and nanoelectromechanical systems. Techniques such as blister tests, atomic-force microscopy and atomic intercalation have been developed to quantify interfacial toughness, bending stiffness and shear strength. Insights into traction-separation relationships and instability patterns have revealed how nanoscale stress redistribution, surface contamination and electrostatic forces modulate adhesion. Understanding these mechanisms is essential for reliable device integration, strain-engineering of electronic properties and the development of flexible, high-frequency resonators.

Research from Nature Portfolio

Recent studies have achieved quantitative control over the mechanical instability of suspended monolayer membranes by applying a push-to-shear strategy that induces dynamic wrinkling and splitting. This approach provides a direct route to measure bending stiffness and to programme nanoscale wrinkle geometries. In parallel, advanced atomic-force microscopy methods have delivered the first quantitative maps of interfacial adhesion in ambient air, isolating the contributions of dispersive and electrostatic forces and demonstrating that simple surface treatments can prevent airborne contamination and restore pristine adhesion levels. Complementing these efforts, circular blister tests on multilayer graphene reveal that interlayer sliding near a crack tip alters the mode mixity of fracture, causing a systematic decrease in adhesion toughness with increasing layer number. Such findings clarify the interplay of bending, stretching and shear in determining interface fracture toughness.

Adhesion Mechanics of Two-Dimensional Materials publication trend

The graph below shows the total number of articles in adhesion mechanics of two-dimensional materials across all publications each year (not limited to Nature Index journals).

Technical terms

Van der Waals forces: Weak, non-covalent attractions between adjacent layers or between a layer and a substrate.

Adhesion energy: The work required to separate two surfaces per unit area, dictating interface stability.

Bending stiffness: Resistance of an ultrathin membrane to out-of-plane deformation, scaling with thickness cubed.

Mode mixity: Ratio of shear to tensile fracture energy at a crack tip, influencing adhesion toughness.

Traction-separation law: Relationship describing stress as a function of interface opening, capturing bond-breaking kinetics.

References

1. Tuning instability in suspended monolayer 2D materials. Nature Communications (2024).
2. Direct measurements of interfacial adhesion in 2D materials and van der Waals heterostructures in ambient air. Nature Communications (2020).
3. Adhesion toughness of multilayer graphene films. Nature Communications (2017).
4. Atomic intercalation to measure adhesion of graphene on graphite. Nature Communications (2016).
5. A stochastic description on the traction-separation law of an interface with non-covalent bonding. Journal of the Mechanics and Physics of Solids (2014).
6. Mechanical, Elastic, and Adhesive Properties of Two‐Dimensional Materials: From Straining Techniques to State‐of‐the‐Art Local Probe Measurements. Advanced Materials Interfaces (2022).
7. Van der Waals interaction affects wrinkle formation in two-dimensional materials. Proceedings of the National Academy of Sciences of the United States of America (2021).