A method to estimate adhesion energy of as-grown graphene in a roll-to-roll dry transfer process

The interfacial adhesion energy of as-grown graphene on its metal growth substrate is an important variable in designing, monitoring, and controlling a roll-to-roll (R2R) graphene transfer process using mechanical peeling. In this study, we develop a novel method to estimate the adhesion energy of as-grown graphene during the R2R dry transfer process. An energy balance model is established to derive the adhesion energy based on web tension and bending curvature measurements. Experiments were conducted under various mechanical peeling conditions. The adhesion energy of as-grown graphene on copper foil was determined to be from 1.22 J/m2 to 2.58 J/m2 depending on the peeling front geometry. The developed adhesion energy estimation method is compatible with the R2R process and can be used to monitor and control the large-scale graphene transfer process with in-process measurements.