Pathways for SO2 dissociation on Cu(100): Density functional theory

Abstract

The dissociation of SO2 on Cu(100) and the diffusion of the co-adsorbed decomposition products S and O were investigated using density functional theory-based calculations. Two dissociation pathways were considered: (P1) and (P2) , the difference being in the formation of the intermediate product SO. It is found that P1 is favored kinetically with a total effective dissociation barrier of 0.78eV compared to P2 which has 1.58eV. The transition state leading to the formation of O+SO is found to be a result of the weakened interaction between the O of SO and the surface while the transition state for breaking SO is seen to be that of the repulsive nature of co-adsorbed S and O. The co-adsorbed S has a lower diffusion barrier of 0.41eV compared to O which has a barrier ranging from 0.49 to 0.95eV. © IOP Publishing Ltd