![]() ![]() In addition, the graphene produced by CVD suffers from poor controllability and low quality. Chemical vapor deposition (CVD) has shown great potential for growing large-sized single-crystal graphene domains ( 8– 12) however, the growth rate with CVD is low, typically less than 20 μm/min, which is obviously not conducive to the fabrication of wafer-sized single crystals. Wafer-sized single-crystal graphene is highly desired and required for numerous applications, especially in electronics and optoelectronics, because grain boundaries between the graphene domains markedly degrade its quality and properties ( 4– 8). Graphene, a one-atom-thick, two-dimensional (2D) crystal, has attracted increasing interest because of its interesting properties, which include a large carrier mobility, high transparency, extremely high thermal conductivity, and high tensile strength ( 1– 3). Using these findings, we propose several strategies for the fabrication of wafer-sized, high-quality, single-crystal graphene. Such edge-structure–dependent growth/etching kinetics of graphene can be well explained at the atomic level based on the concentrations of the kinks on various edges and allow the evolution and control of the edge and morphology in single-crystal graphene following the classical kinetic Wulff construction theory. We have observed that both the growth and the etching rates of a single-crystal graphene domain increase linearly with the slanted angle of its edges from 0° to ∼19° and that the rates for an armchair edge are faster than those for a zigzag edge. We demonstrate the growth of single-crystal graphene domains with controlled edges that range from zigzag to armchair orientations via growth–etching–regrowth in a chemical vapor deposition process. The edges of graphene, which are the sites at which carbon accumulates in the two-dimensional honeycomb lattice, influence many properties, including the electronic properties and chemical reactivity of graphene, and they are expected to significantly influence its growth. The controlled growth of large-area, high-quality, single-crystal graphene is highly desired for applications in electronics and optoelectronics however, the production of this material remains challenging because the atomistic mechanism that governs graphene growth is not well understood. ![]()
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