Defects guided wrinkling in graphene on copper substrate

Pristine graphene depositing on metallic substrates often wrinkles when the film-substrate system undergoes a temperature drop from the chemical vapor deposition (CVD) chamber to ambient environment. The pattern of wrinkles is governed by the crystallographic planes of the substrates and the defects in the film. In this paper, we report how commonly seen Stone-Wales defects and grain boundaries (GBs) influence the morphology of graphene on different planes of single crystalline copper substrate. Stone-Wales defects weaken the bending stiffness in graphene, and result in wrinkling along the defect direction. In the presence of GBs, primary wrinkles are always parallel to the GB direction, and there are also secondary wrinkles perpendicular to the GB. In combination with planes of the substrate and the orientation of defects, we demonstrate that we may manipulate wrinkling patterns for possible engineering applications. (C) 2018 Elsevier Ltd. All rights reserved