Mechanical properties of hydrogenated ψ-graphene

Context Hydrogenation is an effective way to open a band gap of the metallic ?-graphene, expanding its application in electronics. Evaluating the mechanical properties of hydrogenated ?-graphene, especially the effect of hydrogen coverage, is also crucial to the application of ?-graphene. Here, we demonstrate the mechanical properties of ?-graphene depend closely on the hydrogen coverage and arrangement. Upon hydrogenation, Young's modulus and intrinsic strength of ?-graphene decrease due to breaking of sp(2) carbon networks. Both the ?-graphene and hydrogenated ?-graphene exhibit mechanical anisotropy. During changing the hydrogen coverage, the variation of mechanical strength of the hydrogenated ?-graphene relies on the tensile direction. In addition, the arrangement of hydrogen also contributes to the mechanical strength and fracture behavior of hydrogenated ?-graphene. Our results not only present a comprehensive understanding of the mechanical properties of hydrogenated ?-graphene, but also provide a reference to tailor the mechanical properties of other graphene allotropes, which are of potential interest in materials science.Methods Vienna ab initio simulation package based on the plane-wave pseudopotential technique was employed for the calculations. The exchange-correlation interaction was described by the Perdew-Burke-Ernzerhof functional within the general gradient approximation and the ion-electron interaction was treated with the projected augmented wave pseudopotential.