Strain induced highly oriented graphene wrinkles

Graphene, a two-dimensional (2D) material, is an important constituent part for the development of mechanic, electronic and photonic systems due to its remarkable properties, however, wrinkling is a ubiquitous phenomenon in 2D membranes. As a 2D material with atomic thickness, graphene is found to be wrinkled easily because of its relatively low bending rigidity, and besides, wrinkle affects graphene's remarkable physical property severely. Despite their prevalence and potential impact on large-scale graphene properties, only a several approaches have been dedicated to control their structural morphology and orientation by transferring graphene onto polymer substrates. Here we report a new route to control the orientation of wrinkles by directly applying external mechanical strains to metal substrates until plastic deformation happens. By changing direction and magnitude of tension strain, wrinkles with different spacing but all with orientations perpendicular to the tensile direction can be obtained. (paper)