NO dissociation on Cu(111) and Cu sub(2)O(111) surfaces: a density functional theory based study

NO dissociation on Cu(111) and Cu sub(2)O(111) surfaces is investigated using spin-polarized density functional theory. This is to verify the possibility of using Cu-based catalyst for NO dissociation which is the rate limiting step for the NO sub(x) reduction process. The dissociation of molecularly adsorbed NO on the surface is activated for both cases. However, from the reaction path of the NO-Cu sub(2)O(111) system, the calculated transition state lies below the reference energy which indicates the possibility of dissociation. For the NO-Cu(111) system, the reaction path shows that NO desorption is more likely to occur. The geometric and electronic structure of the Cu sub(2)O(111) surface indicates that the surface Cu atoms stabilize themselves with reference to the O atom in the subsurface. The interaction results in modification of the electronic structure of the surface Cu atoms of Cu sub(2)O(111) which greatly affects the adsorption and dissociation of NO. This phenomenon further explains the obtained differences in the dissociation pathways of NO on the surfaces.