Large-scale and low cost synthesis of graphene as high capacity anode materials for lithium-ion batteries

Graphene has emerged as an intriguing and attractive functional material for a wide range of applications, owing to its unique physical, chemical and mechanical properties. Herein, we report large-scale production of high quality single crystalline graphene sheets based on the ambient pressure chemical vapor deposition (APCVD) method using acetylene (C2H2) as the carbon source and coral-like iron with body-centered-cubic structure as the catalyst. The process can be scaled up for large quantity production at a low cost. The optimum APCVD temperature has been identified to be 850°C, which is much lower than that catalyzed by other metals. Transmission electron microscopy (TEM), atomic force microscopy, Raman spectroscopy and X-ray photoemission spectroscopy characterizations show the single crystalline and high quality nature of the as-prepared graphene produced by the bottom-up APCVD approach. A new horizontal “dissolution–deposition–growth” mechanism is proposed and verified by high resolution TEM. When applied as anode materials in lithium ion batteries, graphene sheets exhibited a high lithium storage capacity and an excellent cyclability. The capability of preparing crystalline graphene on a large scale with low cost opens an avenue for technological applications of graphene in many fields.