Effects of Confinement on Oxygen Adsorbed between Pt(111) Surfaces

Density functional theory is used to investigate the interaction between Pt (111) surfaces, clean and in the presence of atomic and molecular oxygen, as a function of the distance between the two surfaces. It is found that the confinement effect produces a series of new physicochemical phenomena, including changes in the surface-subsurface distance between the approaching surfaces, variations in the adsorption energy of O and O-2, and dissociation of molecular oxygen when the separation between surfaces becomes lower than particular threshold distances. It is suggested that these findings may be useful for designing novel devices for catalysis and sensors, and to elucidate the role of cracks in surface degradation behavior.