We report that single-layered and single-crystalline graphene flakes (GFs) with highly regular and hexagonal symmetric patterns can be grown on a liquid copper surface using a CH4 chemical vapor deposition (CVD) method. Different morphologies of these GFs can be precisely tailored by varying the composition of inert gas/H2 carrier gas mixture, and the GF edges can be continuously tuned over the full spectrum from negative to zero to positive curvature in a controllable way. This study provides a well-behaved two-dimensional crystal growth system mimicking snowflakes, opening rich opportunities for engineering graphene patterns and studying graphene structure/property relationships.
- Bin Wu
- Dechao Geng
- Yunqi Liu