Role of Functionalized Graphene materials in Adsorption of SO2 and SO3: A Quantum DFT approach

In this work, we employ first-principles Density Functional Theory (DFT) calculations to systematically investigate the electronic properties, adsorption configurations, and sensing mechanisms of SO₂ and SO₃ molecules on graphene surfaces functionalized with hydroxyl and carbonyl groups. Various graphene-based materials are evaluated, including pristine, defective, boron-phosphorus co-doped, and oxidized graphene nanosheets.Pristine graphene historically suffers from weak physisorption and negligible charge transfer toward sulphur oxides.Notably, due to strong chemisorption, the adsorption energy for SO₃ on graphene oxide increases by a factor of 17 compared to pristine graphene.This study shows that defects and surface functionalization significantly enhance graphene's gas-sensing performance. Graphene oxide exhibits strong chemisorption for SO₃ and moderate chemisorption for SO₂, with superior adsorption energy, quick recovery time, and tunable properties, making it a promising material for SOx sensing.