Adsorption behavior of SO2 on vacancy-defected graphene: A DFT study

The adsorption of an SO2 molecule on the perfect and point-defective graphene surfaces were investigated using density functional theory (DFT). The geometric structure, adsorption energy, charge transfer, and electronic properties were calculated and analyzed to characterize the effect of vacancy on the adsorption process of SO2 on the graphene. The result indicated that the presence of vacancy enhanced the adsorption stability with the larger adsorption energy and net charge transfer compared to that of perfect graphene. Moreover, the SO2 molecule on different adsorption sites exhibited dissimilar states because of the adsorption. Furthermore, the results of the electronic properties revealed that the adsorption of SO2 induced an opening of the band gap.