Effect of the interface on mechanical and fracture properties of lateral graphene/hexagonal boron-nitride heterostructure: A molecular dynamics study

Graphene (Gr) and hexagonal boron-nitride (hBN) based heterostructures are a unique class of materials with unique mechanical and electronic properties. In the first of its kind, the present article employs the Tersoff potential-based molecular dynamics simulations to investigate the effect of interface on the mechanical and fracture properties of three different interface systems, namely hexagonal (6|6), pentagon-heptagon (5|7) and heart-shaped (HS). The results from this study indicate that the interface deteriorates the mechanical properties of Gr and hBN nanosheets, and the heterostructures have slightly reduced failure stress and strain as compared to pristine Gr or hBN nanosheets. However, fracture properties of interface systems exhibit monotonic decrease/increase or considerable improvement in their values depending upon the interface type and distance of crack from the interface. This deterioration or improvement in fracture properties may be attributed to the altered distribution of atomic stress per atom and the misalignment angle, which reduces the strain-induced change in critical bond length. Finally, these establish the mechanical robustness of these heterostructures, which may be very useful in designing Gr/hBN-based tailored nanocomposites.