石墨烯优异的电学、力学特性使其在电子学等领域有着重要的潜在应用。目前制备石墨烯的方法主要有剥离法、外延法、化学气相沉积法（CVD）等。前两种方法效率低，不适于大量制备；而CVD法的产物通常为多晶结构，大量晶界的存在导致石墨烯质量和性能大幅下降。因此，大面积单晶制备技术的缺乏正成为制约石墨烯相关研究及应用的重要瓶颈。本项目将采用等离子体在低温下制备较大面积的单晶石墨烯。研究的重点在于外加电场和电流对铜箔衬底催化特性的影响，放电产生的活性粒子的空间分布及其对单晶石墨烯成核和生长的作用。通过此项研究，我们希望掌握等离子体低温制备大面积单晶石墨烯的方法，在500℃甚至更低温度条件下实现毫米-厘米尺度单晶石墨烯的制备；同时，我们还希望进一步探索等离子体制备单晶石墨烯中关键的物理机制，为今后更大尺度单晶石墨烯的制备奠定基础。

Graphene has extraordinary electric and mechanical properties, which makes it a good candidate for many applications in fields such as electronics and so on. Currently, graphene can be obtained by mechanical exfoliation, epitaxial growth, and chemical vapor deposition (CVD). The former two methods are incapable of synthesizing large area graphene; while the CVD method often produces multi-crystalline graphene; the large amount of crystal boundaries therein cause deterioration of graphene quality and performances. Therefore, fabrication of large area single crystal graphene is very important for graphene research and applications. In this project, we will use plasma to synthesize large area single crystal graphene under lower temperature. To reach the goal, we have to clarify how the catalyzing performances of Cu substrates vary when there is external electric field or electric current; what kind of particles are produced by the plasma and how they spread; how these particles behave during the graphene nucleation and growth. We hope to find out the method of fabricating large scale single crystal graphene using plasma, and manage to obtain millimeter ~ centimeter sized single crystal graphene under 500 ℃ or even lower temperature. Furthermore, we hope that critical physical processes for synthesizing single crystal graphene by plasma can be clarified, which will facilitate the growth of even larger single crystal graphene.