Pyridinic Dominance N-Doped Graphene: A Potential Material for SO₂ Gas Detection

The sensors based on graphene have shown great promise in the detection of toxic air pollutants that are detrimental to nature and create risks to human health. Many recent experimental and computational efforts have been dedicated to sensor concepts incorporating pure graphene, graphene oxide, and doped graphene. Herein, a combination of spin-polarized density functional theory (DFT) with van der Waals correction and ab initio molecular dynamics (AIMD) approaches are utilized to assess the gas sensing potential of pyridinic dominance N-doped graphene (PNG) toward SO₂ detection. The potential of PNG systems as SO₂ sensing can be explored through an in-depth analysis of adsorption energies, electronic parameters, charge transfer, selectivity, and thermal stability. It is further demonstrated that external strains and the modulation of external electric fields are two effective ways to modify the adsorption strength. In light of these findings, our studies suggest that PNG monolayers have the potential to be an essential substrate for the detection of SO₂.