单层和双层石墨烯的可控制备和结构表征

Synthesis and Structural Characterization of Single-and Bi-layer Graphene

以甲烷作为碳源,采用化学气相沉积方法低压下在两种不同厚度的铜箔上生长出石墨烯。利用光学显微镜、拉曼光谱、扫描电子显微镜对石墨烯的结构、形貌和层数进行了表征。结果表明,可以通过调控反应的生长参数来控制石墨烯的层数,实现了单层石墨烯膜、双层石墨烯岛以及双层石墨烯膜的可控制备。并对不同层数石墨烯生长的机制进行初步的分析。

The single-and bi-layer graphene were synthesized on substrate of Cu foil bychemical vapor deposition （CVD）. The impacts of the deposition conditions, including the pressure, flow rates of CH4, H2 and Ar, substrate and annealing temperatures and times,and Cu foil thickness, on the number of layer and microstructures of the graphene were evaluated. The graphene was characterized with optical microscopy, Raman spectroscopy, and scanning electron microscopy. The results indicate that the number of graphene layer can be controlled by adjusting the deposition conditions. For instance, bi-layer graphene, 20 - 30 μm in size, was synthesized at 1000℃ and 1.0 × 104 Pa for 5 rain on 25 tan Cu foilwith CH4, H2 and Ar flow rates of 0.5,30.0, and 500 mL/min, respectively, and annealed at 1000℃ for 30 min. The singlelayer graphene film and bilayer graphene islands were also synthesized. The possible mechanisms responsible for the growth of bilayer graphene were also tentatively discussed.