Chemical Vapor Deposition Growth of Porous Trilayer Graphene.

Trilayer graphene (TLG) has recently attracted growing interest due to its unique electronic energy band structure. The preparation of high-quality large-area TLG would be important for the investigation of electronic properties and applications. However, it is still challenging to simply and effectively prepare TLG. Here, we propose an approach for the growth of large-area TLG domains on a liquid Cu substrate by chemical vapor deposition. Under the combined effect of O2 and high proportion H2 flow, the "self-limiting growth mode" of graphene on the liquid Cu surface was broken, and the vertical growth of graphene was realized. Porous TLG was achieved in this dynamic equilibrium process of H2 etching graphene and O2 accelerating graphene growth. The morphology, crystallinity, stacking order, and uniformity of the ABA-stacked TLG were evaluated by optical spectroscopy, Raman spectroscopy, and transmission electron microscopy. The present study takes a step toward the controlled TLG preparation.