Synthesis of single- and few- layer graphene by chemical vapor deposition of methane on copper and platinum

Graphene has been in the spotlight of research activity for the past decade, this two-dimensional lattice of carbon atoms has strong SP2 covalent bonds that give the material characteristics unmatched by any other substance in terms of mechanical strength, electrical and heat conductivity, as well as flexibility. This project explored the synthesis of Graphene using chemical vapor deposition (CVD), a process well known for its ability to produce high quality, defect-free solid materials. The system was modified to chemically deposit Methane onto Platinum and Copper catalysts at temperatures nearing 1040° C. The resulting samples were characterized using Raman Spectroscopy, the Raman spectrums provide essential information regarding the number of layers in the Graphene structure and whether or not the structure is free of defects. The analyzed Raman spectrums of Graphene on platinum indicate that the relationship between the flow rate and the intensity peak ratio of the 2D/G bands as well as the growth time and the location of the G-band are linear, however, the growth time seems to have less of a clear influence on the intensity peak ratio due to factors like the high solubility of carbon in Pt, the deposition of amorphous carbon near the grain boundaries and the size of the carbon grains themselves. The Raman spectrums of two of the copper samples show G- and 2D- bands that are fitted in the shape of a Lorentzian function, the bands are located near 2710 CM-¹ and 2712 CM-¹ with line widths of 36 CM-¹ and 34 CM-¹ respectively, the G-bands are located near 1590.3 CM-¹ and 1589 CM-¹, with 2D/G intensity peak ratios of ~1.22 and ~1.92 respectively. The D/G intensity peak ratios of both samples were near ~0.07 which is a clear sign that the Graphene structure formed on the surface is defect-free.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofUnreviewedUndergraduat