In this work, density functional theory calculations are performed to examine the catalytic oxidation ofSO2in the presence of O2molecule over carbon-doped hexagonal boron nitride nanosheets (h-BNNSs).The SO2oxidation over these surfaces is characterized as a two-step mechanism; (a) SO2þ O2/SO3þ O* and (b) SO2þ O* / SO3. According to the obtained results, the activation energies and reactionmechanism depend greatly on the substitution site of the C-doped h-BNNS. That is, the catalytic activityof C atom located on top of the B-vacancy site of h-BNNS is larger than that of on top of the N-vacancy.Moreover, it is found that the energy barriers for the oxidation of SO2are considerably decreased in anaqueous solution. For a given substrate, the activation energy for the oxidation of H2SO3is much largerthan that of SO2, suggesting that the direct conversion of SO2to SO3should be the main reaction pathwayfor the oxidation of SO2. The results of present study could contribute to design highly active BN-basedcatalysts to oxidize SO2molecule.
