First-principles study of oxygen adsorbed on Au-doped RuO₂ (110) surface

Density functional theory calculations are carried out to identify various configurations of oxygen molecules adsorbed on the Au-doped RuO₂ (110) surface. The binding energy calculations indicate that O₂ molecules are chemically adsorbed on the coordinatively unsaturated Ru (Ru_cus) sites and the bridge oxygen vacancies on the Au sites. Transition state calculations show that O^* can exist on the Ru_cus site by O₂^* dissociation and diffusion. The calculations of the reaction path of CO indicate that the reaction energy barrier of CO adsorbed on Au with lattice oxygen decreases to 0.28 eV and requires less energy than that on the undoped structure.