Fig. 2

Optical images and Raman spectra (inserts) of a amorphous carbon as the result of an attempted graphene synthesis for 7 min C₂H₂ exposure on 50 nm pure Ni catalyst at 450 °C and b successful graphene synthesis following the same parameters as a on codeposited Ni-Au catalyst, please note the dark spot in the top of image b is an area of multilayer graphene and was captured to add contrast to help identify the surrounding monolayer area. There is an obvious improvement created by the addition of 1 wt% Au as this is the only variable changed to allow for the drastic shift from amorphous carbon to graphene. Labeled in a are the key peaks used for graphene characterization. For b, we calculate I_2D:G = 1.2, FWHM_2D = 48.5, I_D:G = 0.68, and I_D:D’ = 5.0