Universality in surface mixing rule of adsorption strength for small adsorbates on binary transition metal alloys

Understanding the adsorption phenomena of small adsorbates involved in surface reactions on transition metals is important because their adsorption strength can be a descriptor for predicting the catalytic activity. To explore adsorption energies on a wide range of binary transition metal alloys, however, tremendous computational efforts are required. Using density functional theory (DFT) calculations, here we suggest a "surface mixing rule" to predict the adsorption energies of H, O, S, CO and OH on bimetallic alloys, based on the linear interpolation of adsorption energies on each pure surface. As an application, the activity of CO oxidation on various bimetallic alloys is predicted from the adsorption energies of CO and O easily obtained by the surface mixing rule. Our results provide a useful tool for rapidly estimating adsorption energies, and furthermore, catalytic activities on multi-component metal alloy surfaces.