Control of the stacking angle (θS) of bilayer graphene (BLG) is essential for fundamental studies and applications of BLG. Especially, the use of chemical vapor deposition (CVD) to grow high-quality BLG requires this control, but methods to achieve it are not available. Here, we found that graphene rotates during the CVD process, and this action can be exploited as a new strategy to control θS. The rotation of graphene was revealed by the population changes of AB-stacked BLG and 30°-twisted BLG upon the growth time change; this change can only be explained by rotation of graphene. The rotation is largely affected by the edge state of graphene which can be tuned by growth temperature. The rotation was observed through experimental results combined with theoretical calculation. The rotation can be blocked or accelerated by controlling the growth temperature, by which highly selective growth of AB-stacked BLG or 30°-twisted BLG can be achieved.
Keywords: bilayer graphene; chemical vapor deposition; graphene edge; graphene rotation; programmed temperature; stacking angle.