Precise control of chemical vapor deposition graphene layer thickness using Ni_xCu_1−x alloys

Abstract

We investigated a simple but effective method to precisely control the desired number of graphene layers on the Ni x Cu 1Àx alloy substrates by thermal chemical vapor deposition. Our method could be utilized to precisely control the number of graphene layers without altering growth conditions such as growth temperature and the cooling rate.Graphene, a two-dimensional nanostructure of sp 2 -bonded carbon atoms, has attracted worldwide interest owing to its novel and unique properties such as its high charge mobility, quantum Hall effect, high optical transparency, exibility, and electrical and thermal conductivities. 1-5 However, the realization of graphene-based optoelectronic, electronic, and chemical devices requires the development of a reproducible, large-scale method to produce single-or few-layer graphene lms with high crystalline quality. In particular, it is well recognized that one of the most promising application areas of graphene is transparent electrodes for solar cells or touchscreen displays. For these applications, precise control of graphene layer growth is essential to achieve uniform electrical and optical properties. Accordingly, intensive efforts have been devoted to developing an economic and reproducible method allowing the synthesis of graphene with the appropriate quality. Since graphene mechanically exfoliated from graphite akes was introduced by Geim et al. in 2004, many graphene synthesis methods have been demonstrated such as chemical exfoliation from bulk graphite powders, chemical reduction from graphene oxides, and chemical vapor deposition. 3,6-11 Among these, chemical

Spanning the “Parameter Space” of Chemical Vapor Deposition Graphene Growth with Quantum Chemical Simulations

“…Ni, Cu, Fe, Co). A number of experiments 63,[126][127][128][129] highlight the potential importance of bimetallic alloy catalysts for graphene (and carbon nanotube) synthesis. However, no mechanistic insights have yet been proposed for these catalysts, or alloy catalysts in general.…”

A dilute Cu(Ni) alloy for synthesis of large-area Bernal stacked bilayer graphene using atmospheric pressure chemical vapour deposition

“…[2][3][4] Amongst the common approaches used to produce AB-stacked bilayer graphene films are the chemical vapour deposition (CVD) which has attracted tremendous research activities due to its ability to produce wafer-scale high-quality graphene films with a controllable number of layers. [5][6][7] In CVD graphene growth, metal substrates are used to promote graphene synthesis by a surface growth mechanism or by segregation (precipitation). 8,9 Metal substrates commonly used for CVD graphene growth include nickel (Ni) and copper (Cu).…”

A wafer-scale Bernal-stacked bilayer graphene film obtained on a dilute Cu (0.61 at% Ni) foil using atmospheric pressure chemical vapour deposition

“…In previous studies, Cu/Ni thin lms and commercial Cu-Ni alloys have demonstrated such capability, including the growth of large-area AB-stacked bilayer graphene. 20,24,25 In these studies, the Cu/Ni thin lms have Ni concentrations >5 at% (ref. 17, 24 and 26) 20,23,25,26 Therefore, the idea of a dilute Cu (0.61 at% Ni) foil is aimed at obtaining high surface concentration of Ni (1 to 3 at%) in Cu (0.61 at% Ni) foil through bulk-to-surface diffusion of Ni while maintaining a low bulk concentration of Ni (<1 at%) in Cu(Ni) foil during hydrocarbon exposure for graphene growth.…”