▎ 摘　　要

Using the first-principles periodic boundary density functional theory along with the Grimme function, this study investigated the vacancy formation in the neck area of a 3-D pillared graphene structure. Three different possible configurations of the monovacancy defect formation were studied on a 3-D pillared graphene in order to explore the role of the monovacancy defect in the structural, electronic, and magnetic properties of each configuration. The density of state (DOS), projected DOS and spin polarization of the defected structures were calculated in order to determine which monovacancy site could have a significant impact on the magnetization of the 3-D pillared graphene. The obtained results at the GGA/revPBE level with a DZP basis set revealed that the influence of changing the position of the monovacancy defects from the graphene sheet to the nanotube part of the 3-D pillared graphene could give rise to greater magnetization. In particular, the monovacancy defects on the graphene (sheet) and nanotube (pillar) parts of the 3-D pillared graphene yielded less magnetization and greater magnetization, respectively. Moreover, the simulation results indicated that the px and pz orbitals had a substantial contribution to the spin polarization in these structures.