Uniform growth of AB-stacked bilayer graphene single crystal by cyclic segregation/dissolution

Large-area growth of AB-stacked bilayer graphene (AB-BLG) single crystal is fundamental for realizing its application in next-generation electronic, optoelectronic and spintronic devices. However, it is difficult to grow uniform bilayer single crystal graphene with complete AB-stacking and full coverage on the low-cost and scalable metal foils. Here, we report a cyclic segregation/dissolution strategy for growing uniform AB-BLG single crystal on the single-crystal Cu/Ni(111) foil. The positive correlation between the carbon solubility in solid metals and temperature was used to realize the reversible growth and etching of graphene for tailoring its structural uniformity. Thus-prepared single-crystal BLG film shows the high bilayer coverage and AB-stacking with the electrical property comparable to that of exfoliated ones. Our strategy provides some useful references for developing precise growth methodology of graphene and other two-dimensional materials.