Potassium and Water Coadsorption on TiO2(110): OH-Induced Anchoring of Potassium and the Generation of Single-Site Catalysts

Description

Potassium deposition on TiO2(110) results in reduction of the substrate and formation of loosely bound potassium species that can move easily on the oxide surface to promote catalytic activity. The results of density functional calculations predict a large adsorption energy (∼3.2 eV) with a small barrier (∼0.25 eV) for diffusion on the oxide surface. In scanning tunneling microscopy images, the adsorbed alkali atoms lose their mobility when in contact with surface OH groups. Furthermore, K adatoms facilitate the dissociation of water on the titania surface. The K-(OH) species generated are good sites for the binding of gold clusters on the TiO2(110) surface, producing Au/K/TiO2(110) systems with high activity for the water-gas shift.

Abstract

US Department of Energy DE-SC0012704

Abstract

Ministerio de Economía y Competitividad CTQ2015-64669- P

Abstract

Junta de Andalucía P12-FQM-1595

Additional details