Graphene Growth on Pt(111) by Ethylene Chemical Vapor Deposition at Surface Temperatures near 1000 K

Abstract

The nucleation and growth of graphene islands on a Pt(111) surface were examined at temperatures near 1000 K. Graphene was grown by chemical vapor deposition of ethylene, and a low-energy electron microscope (LEEM) was used to image the growing graphene islands with resolution of 10 nm and to perform spatially localized electron diffraction. It is shown that graphene grows bidirectionally over the step edges of Pt, and its formation can induce substantial changes in the platinum surface morphology. Average size and density of graphene islands strongly depend on surface temperature during deposition. Postdosing Auger electron spectroscopy was employed as a complementary macroscopic technique to measure the total carbon deposited as a result of ethylene dissociative sticking and decomposition. The initial dissociative sticking coefficient S0(Tg = 300 K, Ts) for ethylene was found to decrease with increasing surface temperature until a temperature of Ts = 850 K was reached whereupon it increased with temperature.