Low-coverage condensation of K on TiO 2(1 1 0) 1 × 1

Abstract

The adsorption site of K on TiO 2(1 1 0) 1 × 1 has been investigated at low coverage (<0.15 ML, where 1 monolayer corresponds to the number of surface unit cells). A combination of surface extended X-ray absorption fine structure (SEXAFS), scanning tunneling microscopy (STM), and non-contact atomic force microscopy (NC-AFM) was used for this purpose. SEXAFS identifies a threefold O hollow site in which K bonds to two bridging O atoms and one in-plane O atom at K–O bond distances of 2.49 ± 0.12 Å and 2.73 ± 0.07 Å. STM and NC-AFM images evidence a condensation of K atoms on either side of the bridging O row.