A 5nm-thick Au film was deposited onto single-layer graphene sheets grown onto Cu. De-wetting of the Au film on the graphene was induced so to form Au nanoparticles. The mean radius, surface-to-surface distance, and surface density evolution of the nanoparticles on the graphene sheets as a function of the annealing temperature were quantified by scanning electron microscopy analyses. These data were analyzed within classical mean-field nucleation theory so to obtain the temperature-dependent Au atom surface diffusion coefficient on graphene:

D(cm2/s) = 8.2 x 10-8exp[-0.31(eV)/kT]

F.Ruffino, G.Cacciato, M.G.Grimaldi: Journal of Applied Physics, 2014, 115[8], 084304