The Study on the Medium-Sized Carbon Islands on Ru(0001) Surface

Abstract

During chemical vapor deposition (CVD) growth of graphene on Ru(0001) surface, a specific C cluster, which has 13 C atoms arranged as three connected hexagons (so called 3-C-6), was supposed to be extremely stable. To verify this, we systemically explored the stabilities of carbon clusters C-N (N = 12, 13, 14) on the Ru(0001) surface by using first principle approach. While, it is surprising that neither 3-C-6 is the ground state of C-13 nor the C-13 cluster shows exceptional stability. So, based on the experimental STM image with C-3v symmetry and a dimmer of 1 nm, the magic cluster was proposed as C-21 or C-21-3C, which have the same core composed of six hexagons and three pentagons, as that studied before. This study is helpful to resolve the debate on the dominating clusters observed during graphene CVD growth and is helpful for understanding the growth mechanism of graphene CVD growth.