Layer-by-Layer Growth of Graphene on Insulator in CO₂-Oxidizing Environment

Since the discovery of graphene by sticking and peeling scotch tape off graphite, it has also been prepared by other methods, such as thermal decomposition of SiC and chemical vapor deposition (CVD) with catalytic layer. Both the exfoliation and CVD methods impose to transfer the graphene layers on other insulating substrates for device applications. We reported that diamond grows in oxygen atmosphere (Yoshimoto M.; Nature1999, 399, 340-342) in which oxidative etching and depositing carbon compete under equivalent conditions. However, oxygen atmosphere is too intense for graphite growth. Although carbon dioxide (CO₂) is produced after hydrocarbon combustion, it can be a gentle and tender oxidant in certain situations. Here, we show the direct growth of graphene on insulating substrates in 100% CO₂ environment and observe its layer-by-layer growth on the stepped edge of an insulating substrate. The direct growth can have a significant advantage of excluding the necessary process of transferring the graphene on the insulating substrate over other common methods.