Carbon clusters near the step of Rh surface: implication for the initial stage of graphene nucleation*
Key Laboratory of Materials Modification by Laser, Ion and
Electron Beams (Dalian University of Technology), Ministry of Education, Dalian
a e-mail: email@example.com
Received in final form: 31 August 2012
Published online: 19 March 2013
To understand the initial nucleation of graphene by chemical vapor deposition along metal step, carbon clusters (N = 1 ~ 24) near Rh (4 3 3) stepwise surface were systemically explored by first-principles calculations. Carbon chains are always more stable than carbon rings on stepped metal surface. Starting from C6, carbon chains prefer two-end passivation on the metal step. A structural transition of carbon clusters from one-dimensional sp chains to two-dimensional sp2 networks are found at C10, which corresponds to the nucleation size at a wide range of chemical potentials. According to these theoretical results, we proposed that appropriately controlling the chemical potential may be helpful for observing the four stable carbon clusters along metal step and improving the quality of graphene.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2013