▎ 摘　　要

We report that the doping of energetic nitrogen cations (N-2(+)) on graphene effectively controls the local N-C bonding structures and the pi-band of graphene critically depending on ion energy E-k (100 eV E-k(c). We further show that one may control the electron charge density of graphene by two orders of magnitude by varying E-k of N-2(+) ions within the energy range adopted. Our DFT-based band calculations reproduce the distinct doping effects observed in the pi-band of the N-2(+)-doped graphene and provide an orbital origin of the different doping types. We thus demonstrate that the doping type and electron number density in the N-2(+) ion-doped SLG can be artificially fine-controlled by adjusting the kinetic energy of incoming N-2(+) ions.