Influence of cooling-induced edge morphology evolution during chemical vapor deposition on H₂ etching of graphene...

In this paper, we studied the influence of edge morphology evolution during the chemical vapor deposition cooling process on H₂ etching of graphene domains. Hexagonal graphene domains were synthesized on a Cu substrate and etched with H₂ at atmospheric pressure. After etching, two kinds of graphene edge morphologies were observed, which were closely associated with the cooling process. A visible curvature was observed at the graphene edges via an atomic force microscope, indicating that the graphene edges sank into the Cu surface during the cooling process, which protected the graphene edges from etching. This work demonstrates the changes in graphene edges during cooling and sheds light on the etching mechanism of graphene edges on a Cu substrate.