Controlled Growth of Bilayer Graphene on Space-Confined Cu Substrates

Bilayer graphene with an AB-stacking sequence has emergedas oneof the promising materials owing to its unique band-gap structureand the fascinating potential in electronic and photonic applications.However, the chemical vapor deposition growth of bilayer grapheneon Cu substrates still suffers from limited bilayer coverage, pooruniformity, and random distribution of the stacking order. Herein,we demonstrated an efficient method to synthesize centimeter-sizedgraphene films with a bilayer ratio of over 80% on space-confinedCu substrates. Moreover, the stacking order of the as-obtained bilayergraphene films was proven to be 100% AB-stacking structure by transmissionelectron microscopy and Raman characterization. Band-gap tunabilityand uniform optical transmittance also confirmed the high qualityof as-obtained bilayer graphene. This work provides a new insightinto the growth of graphene with controlled layer thickness and anew choice for the production of AB-stacked bilayer graphene films.

Automated summary

An efficient method was demonstrated to synthesize centimeter-sized graphene films with over 80% bilayer ratio on confined Cu substrates. The obtained bilayer graphene films showed a 100% AB-stacking structure confirmed by transmission electron microscopy and Raman characterization. The high quality of the bilayer graphene films was also evidenced by tunable band-gap and uniform optical transmittance. This work provides new insights into graphene growth with controlled layer thickness and a new choice for AB-stacked bilayer graphene film production.