Low-Temperature Synthesis of Graphene by ICP-Assisted Amorphous Carbon Sputtering

Abstract

Efficient and affordable synthesis of graphene at low temperatures remains a significant challenge that potentially limits the use of this material in real-life applications. We describe here a simple, efficient, highly controllable technique to synthesize graphene by sputtering carbon from a solid source with the assistance of inductively coupled plasma (ICP), followed by controllable low-temperature annealing at about 550 oC. Raman scattering and X-ray diffraction characterizations have revealed the formation of a few layer graphene of high quality, confirmed by a low (∼0.48) ID/IG ratio. Raman analysis of samples formed at various annealing temperatures has revealed an upper limit for annealing temperature of 585 oC, beyond which the formed graphene reversibly dissolves in the metal. The ICP-assisted process was innovatively employed to improve the quality of thus-fabricated graphene at low temperatures. The mechanism of graphene formation was attributed to the metal induced graphitization in combination with the carbon precipitation onto the catalyst surface.