Orientation Sensitive Nonlinear Growth of Graphene: A Geometry-determined Epitaxial Growth Mechanism

TL;DR

This paper reveals that the nonlinear growth of graphene on various metal substrates is primarily governed by geometric factors rather than specific carbon-metal interactions, enabling accurate predictions of epitaxial growth behavior.

Contribution

It introduces a geometry-determined kinetic Monte Carlo model that explains the orientation-sensitive growth of graphene across different substrates.

Findings

Growth kinetics are dictated by substrate geometry, not chemical interactions.

Lattice mismatch patterns influence macroscopic epitaxial growth.

The model accurately predicts graphene growth on Ir(111) surface.

Abstract

Although the corresponding carbon-metal interactions can be very different, a similar nonlinear growth behavior of graphene has been observed for different metal substrates. To understand this interesting experimental observation, a multiscale $\lq\lq$standing-on-the-front" kinetic Monte Carlo study is performed. An extraordinary robust geometry effect is identified, which solely determines the growth kinetics and makes the details of carbon-metal interaction not relevant at all. Based on such a geometry-determined mechanism, epitaxial growth behavior of graphene can be easily predicted in many cases. As an example, an orientation-sensitive growth kinetics of graphene on Ir(111) surface has been studied. Our results demonstrate that lattice mismatch pattern at the atomic level plays an important role for macroscopic epitaxial growth.