▎ 摘　　要

The electronic structure of the interface graphene/Ni(111) substrate is reinterpreted based on X-ray photoelectron spectroscopy depth profile study. Using a newly developed Argon gas cluster ion beam sputtering system, we probed the variation of C 1s, Ni 2p core level peaks, valence band, and Ni L3M45M45 Auger transition lines described within Wagner plot methodology with the aim to shed light on the graphene growth mechanism on nickel substrate. We found the presence of thin carbon free nickel subsurface layer located between graphene layers and bulk nickel carbide. The gradient change in the d-band electronic structure through this subsurface layer affects the intrinsic properties of nickel substrate (carbon solubility and diffusivity) and may play a crucial role in the graphene growth mechanism.