The complementary graphene growth and etching revealed by large-scale kinetic Monte Carlo simulation

Abstract

To fully understand the kinetics of graphene growth, large-scale atomic simulations of graphene islands evolution up to macro sizes (i.e., graphene islands of a few micrometers or with billions of carbon atoms) during growth and etching is essential, but remains a great challenge. In this paper, we developed a low computational cost large-scale kinetic Monte Carlo (KMC) algorithm, which includes all possible events of carbon attachments and detachments on various edge sites of graphene islands. Such a method allows us to simulate the evolution of graphene islands with sizes up to tens of micrometers during either growth or etching with a single CPU core. With this approach and the carefully fitted parameters, we have reproduced the experimentally observed evolution of graphene islands during both growth or etching on Pt(111) surface, and revealed more atomic details of graphene growth and etching. Based on the atomic simulations, we discovered a complementary relationship of graphene growth and etching—the route of graphene island shape evolution during growth is exactly the same as that of the etching of a hole in graphene and that of graphene island etching is exactly same as that of hole growth. The complementary relation brings us a basic principle to understand the growth and etching of graphene, and other 2D materials from atomic scale to macro size and the KMC algorithm is expected to be further developed into a standard simulation package for investigating the growth mechanism of 2D materials on various substrates.

Chemical Etching of Screw Dislocated Transition Metal Dichalcogenides

“…The surface oxidation and etching of WSe 2 single crystals can improve their solar conversion performance . Furthermore, because etching can be generally thought of as the reverse process of growth, the experimental and computational studies of etching also allow us to better understand the growth mechanisms of layered materials. , The simulations of growth and etching of 2D materials can reproduce experimental observations in the growth of single crystal and multiple graphene grains, which can guide more rationally controlled growth. , …”

Growth and Etching of the Grain Boundaries in Polygonal Graphene Islands

“…Etching is a reversible growth process that can be used to achieve the detailed information on growth kinetics [34] . As shown in Figure 4a, a hexagonal shape of GI on Cu surface is transmitted to be a near‐round one by etching in H 2 circumstances, which complied with the fast‐etching edges with ∼19° slanted angle from zigzag edges [35] . As the etching proceeds, a hexagonal etched hole is generated in the center of one GI (Figure 4b).…”

“…[34] As shown in Figure 4a, a hexagonal shape of GI on Cu surface is transmitted to be a near-round one by etching in H 2 circumstances, which complied with the fast-etching edges with ~19°s lanted angle from zigzag edges. [35] As the etching proceeds, a hexagonal etched hole is generated in the center of one GI (Figure 4b). Besides the central hexagonal hole, some hexagonal etched holes are observed at the outside GI.…”

Graphene‐Based Nanomaterials for Biomedical, Catalytic, and Energy Applications

“…It can also simulate the growth or etching of graphene islands of up to 10 μm size range using a single computer core and carefully fitted parameters. [27] Furthermore, deciding the appropriate forcefield for the simulation study is another critical parameter that bridges the gap between computational experiments and engineering applications. Recently, Mohamed et al have performed ab initio molecular dynamics (AIMD) simulations using the forcefield parameters from DFT calculations using the DDEC (Density Derived Electrostatic and Chemical partitioning) method for large-scale, accurate modeling of graphene oxide.…”