A submonolayer amount of titanium was deposited and subsequently oxidized in situ on a clean polycrystalline nickel foil in ultrahigh vacuum. Temperature-programmed desorption revealed the activation energy for CO desorption was reduced significantly by the presence of titania surface species. The titania-containing Ni surface showed three binding states for dissociative hydrogen adsorption. Adsorption into the strongest of these three states was an activated process. These results suggest the apparent suppression of CO and H2 adsorption typically observed at 300 K for titania-supported group 8 metals may be due to the existence of titania species on the surfaces of the metal particles.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry