Investigation on graphene growth by roll-to-roll chemical vapor deposition

Both batch-to-batch (B2B) and roll-to-roll (R2R) processes can be used for mass production of graphene films. Because of the simplicity of equipment, the B2B process is more commonly used in laboratory research. In contrast, the R2R process is more industrially preferred because it is easier to automate and more compatible with the subsequent transfer process. Up to now, the research on R2R process has mainly focused on the design of the reactor or the loading configuration, but the in-depth understanding on the growth kinetics is lack. In this paper, we investigated the evolution of graphene growth and revealed that the graphene domain density grown by the R2R process was larger than that by the B2B process with the same reaction parameters, which was attributed to different reaction profiles between the two processes. Furthermore, the defective graphene could be healed with elongated reaction time. With the optimized R2R process, graphene films with quality comparable to those grown by conventional B2B process could be achieved. Our research will promote the development of the mass-production technique for graphene films.