Theoretical study of structure sensitivity on ceria-supported single platinum atoms and its influence on carbon monoxide adsorption.

Density functional theory (DFT) calculations explore the stability of a single platinum atom on various flat, stepped, and defective ceria surfaces, in the context of single-atom catalysts (SACs) for the water-gas shift (WGS) reaction. The adsorption properties and diffusion kinetics of the metal strongly depend on the support termination with large stability on metastable and stepped CeO(100) and (210) surfaces where the diffusion of the platinum atom is hindered. At the opposite, the more stable CeO(111) and (110) terminations weakly bind the platinum atom and can promote the growth of metallic clusters thanks to fast diffusion kinetics.