Dynamic observation of layer-by-layer growth and removal of graphene on Ru(0001)

Graphene growth and dissolution on Ru(0001) was dynamically imaged by low energy electron microscopy (LEEM) and photoemission electron microscopy (PEEM). It was found that multilayer graphene grows on the metal surface in a layer-by-layer mode and the removal of graphene multilayers also occurs one layer after another. The topmost surface of the formed multilayer graphene is physically continuous as indicated by scanning tunneling microscope (STM) images. Accordingly, a bottom-up growth mechanism of multilayer graphene on Ru(0001) was proposed, which would help to prepare graphene overlayers with controlled thickness.