UC Santa Barbara

We report the results of density-functional theory calculations for the dissociative adsorption of methane (DAM) on CaO(001) doped with Li, Na, K, and Cu. The presence of these dopants lowers the energy of oxygen-vacancy formation, increases the energy of the DAM reaction, and lowers the activation energy for DAM. We performed the same calculations for a stepped CaO(001) surface doped with Na and found that Na prefers being located at a step and the activation energy for DAM is lower at this step than on the doped, flat surface. We propose that such trends are valid for all oxides doped with lower-valence dopants. © 2013 American Chemical Society.