Patterned arrangement regulated mechanical properties of hydrogenated graphene

Abstract

Molecular dynamics simulations have been performed to systematically investigate the effects of hydrogen arrangement on the mechanical properties and failure process of four hydrogenated graphene sheets with mosaic shapes (circle, square, rhombus and triangle) with same H-coverage. Compared to random hydrogenation, the interface of sp2 and sp3 bonds provided by mosaic-like hydrogen pattern retards the deterioration of intrinsic strength caused by hydrogenation. For graphene with void defects, patterned hydrogenation surrounding the void edge will decrease edge stress. The shielding effect of hydrogenation on stress concentration provides noticeable amelioration of mechanical properties, which is sensitive to the void shape because of the difference in stress concentration. Our results suggest that the mechanical properties are tunable by manipulating the arrangement of hydrogen atoms. Patterned hydrogenation can be fully used for optimized characteristics of nanodevices fabricated from hydrogen functionalized graphene.