▎ 摘　　要

The electronic and mechanical properties of a penta-graphene monolayer (PGM) in attendance and nonattendance of oxygen impurities were investigated using the SIESTA computational code, based on density functional theory calculations. The results of the first-principles (ab-initio) calculations show that PGM in the nonattendance of oxygen atoms is a semiconductor with indirect band gap. By adding the oxygen, the bandgap size of PGM changes. Analyzing the results indicates that oxygen absorption increases the stability of the structure. The results display that, the addition of oxygen atoms affects the electrical and mechanical properties of penta-graphene, such as converting the band structure from semiconductor to insulating, reducing Young's modulus, and changing the Poisson's coefficient sign. Penta-graphene has received a lot of attention from researchers as a mechanical metamaterial or auxetic material due to its negative Poisson coefficient.