Hydrogen etching effect on single-crystal graphene domains

In this paper, the anisotropic hydrogen etching effect on chemical vapor deposited sing-crystal graphene domains was reported. After synthesized by chemical vapor deposition on copper foils, the graphene domains were exposed to a mixed gas flow of argon and hydrogen for etching. By varying the etching temperature from 800°C to 1050°C, hexagonal openings inside the graphene domains were found on hydrogen etched samples. The dependence of substrate was then studied and the result indicated that copper was necessary in the etching process as catalyst. At last, etching experiments were performed on high quality single-crystal graphene domains, and the result showed that the hexagonal single-crystal graphene domains were etched to circular.