Dynamics of graphene growth on a metal surface: a time-dependent photoemission study

Applying time-dependent photoemission we unravel the graphene growth process on a metallic surface by chemical vapor deposition (CVD). Graphene CVD growth is in stark contrast to the standard growth process of two--dimensional films because it is self-limiting and stops as soon as a monolayer graphene has been synthesized. Most importantly, a novel phase of metastable graphene was discovered that is characterized by permanent and simultaneous construction and deconstruction. The high quality and large area graphene flakes are characterized by angle-resolved photoemission proofing that they are indeed monolayer and cover the whole 1$\times$1 cm Nickel substrate. These findings are of high relevance to the intensive search for reliable synthesis methods for large graphene flakes of controlled layer number.