Hexagonal single-crystal graphene, with edges parallel to the zig-zag orientations, was synthesized using ambient-pressure CVD on polycrystalline Cu foils. The electronic properties of such grains were measured as well as that of individual graphene grain boundaries which formed when two grains merged during growth. The grain boundaries were visualized using Raman mapping of the D band intensity, and it was shown that individual boundaries between coalesced grains impeded electrical transport in graphene and induced prominent weak localization, indicative of intervalley scattering in graphene.

Electronic Properties of Grains and Grain Boundaries in Graphene Grown by Chemical Vapor Deposition. L.A.Jauregui, H.Cao, W.Wu, Q.Yu, Y.P.Chen: Solid State Communications, 2011, 151[16], 1100–4