▎ 摘 要
In this work, we present a spin-polarized density functional theory study on the structural, electronic, and magnetic properties of a penta-graphene (PG) sheet with substitutional doping of the boron or nitrogen (B/N) atom combined with a vacancy defect. In all cases, we consider the defective sites of the sp(2)-hybridized carbon (C) atom from the top monolayer of the PG composite layer. Our analysis of band structure and density of states calculations shows that the band gap of the pure PG can be engineered within the range of 0.55-0.98 eV, depending on the defect type and location. Further investigation of the band structures shows that B/N doping and a single vacancy defect of the PG sheet consistently produce an intermediate excitation state through the forbidden band, which improves the conductivity of the sheet. The magnetic moments are investigated by using Mulliken population analysis and checked by visualizing the spin-polarized charge density; it is found that B/N-doped PG with and without the existence of vacancies are spin-polarized, in contrast to the vacancy defect, which remains symmetric and nonmagnetic.