A first-principle study of the adsorption behavior of NO gas molecules on pristine and Al-doped penta-graphene

Penta-graphene (PG) has a large ratio of surface to volume and an intrinsic quasi-direct band gap that may benefit for the application of semiconductor sensors. In order to investigate the adsorption behavior of nitric oxide (NO) molecule on the surface of PG, in this study, the adsorption energy, charge transfer and adsorption distance of NO at different locations of pristine and Al-doped PG are investigated by the means of first principle calculations. Results show that the orientation of NO gas molecule has obvious influence on the adsorption behavior in some way. Compared with the pristine PG system, the Al-doped PG system has much higher adsorption energy and shorter adsorption distance. Moreover, the simulation result of total electron density of NO gas on Al-doped PG shows that chemical bonds may exist in the process of NO molecular adsorption, while NO molecule is physically adsorbed on the pristine PG. Furthermore, the result of density of states (DOS) shows that orbital hybridization could be formed between NO and Al-doped PG, indicating that the chemical adsorption occurs.