A hot-pressing pretreatment of Cu substrate and dry transfer method of multilayer-stacked graphene for ionic electroactive polymers

Abstract We herein report the development of an ionic electroactive polymer (IEAP) actuator based on a high quality graphene electrode with minimized surface damage through the use of a hot-pressing (HP) pretreatment process for copper substrate in addition to the dry transfer method for a multilayer-stacked graphene electrode. This HP process for pretreatment of the Cu foil was developed to ensure high-quality graphene growth, and the production of larger grain sizes than those normally obtained following conventional pretreatment methods. We also demonstrate that compared to the conventional wet transfer process based on poly(methyl methacrylate) and the roll-to-roll direct dry transfer method minimizes surface damage of graphene. A 5-layer stacked graphene electrode was prepared and it exhibited a low sheet resistance and flexibility, in addition to the ability to prevent water evaporation during electrical stimulation, thereby improving both the electrode performance and the durability. This 5-layer stacked graphene-based IEAP actuator prepared using HP pretreatment and a dry transfer method exhibited enhanced actuation performances, including a larger bending curvature, a larger maximum bending deformation, and an improved durability.