▎ 摘　　要

Metal growth on graphene has many applications. Transition metals are known to favor three-dimensional (3D) cluster growth on graphene. Copper is of particular interest for cost-effective surface-supported catalysis applications and as a contact material in electronics. This paper presents an in situ real-time study of Cu growth kinetics on graphene covering all stages preceding formation of a continuous film performed by laboratory-based grazing-incidence small-angle x-ray scattering (GISAXS) technique. In particular, nucleation and 3D cluster growth, coalescence, and percolation stages were identified. The cluster nucleation saturates after reaching a density of 10(12) cm(-2) at approximate to 1 monolayer thickness. A Kratky plot and a paracrystal model with cumulative structural disorder were necessary to evaluate properly cluster growth and coalescence, respectively. The power law scaling constants 0.27 +/- 0.05 and 0.81 +/- 0.02 of the temporal evolution of Cu cluster size suggest the growth of isolated clusters and dynamic cluster coalescence keeping the cluster shape, respectively. Coalescence and percolation thresholds occur at Cu thicknesses of 2 +/- 0.4 and 8.8 +/- 0.7 nm, respectively. This paper demonstrates the potential of laboratory-based in situ GISAXS as a vital diagnostic tool for tailoring a large variety of Cu nanostructures on graphene based on an in situ Cu growth monitoring which is applicable in a broad range of deposition times.