AVS 56th International Symposium & Exhibition
    Surface Science Monday Sessions
       Session SS2-MoM

Paper SS2-MoM5
Controlled Manipulation of Oxygen Vacancies on TiO2(110)-1x1 Using LT-STM

Monday, November 9, 2009, 9:40 am, Room N

Session: TiO2 Surfaces and Interfaces
Presenter: D. Acharya, Brookhaven National Laboratory
Authors: D. Acharya, Brookhaven National Laboratory
P.W. Sutter, Brookhaven National Laboratory
Correspondent: Click to Email
Titanium dioxide (TiO2) – widely used in, photocatalysis, heterogeneous catalysis, gas sensors, and solar cells – has become the prototype material for studying the chemical reactivity of metal oxide surfaces. Oxygen vacancies are among the primary chemically active defects on this surface, as well as on other reducible transition metal oxides. We report the controlled manipulation of individual O-vacancies (Ov) on reduced TiO2 (110)-1x1 in low temperature scanning tunneling microscopy. Using localized voltage pulses, the hopping of oxygen vacancies can be controlled precisely along the bridging oxygen rows. We apply this single-vacancy manipulation to study the interaction of closely spaced vacancies, and to establish the possibility of forming highly reactive double and triple Ov clusters. The occurrence of such defects with exposed low-coordinated Ti atoms has implications on the reactivity of TiO2(110) and of similar metal-oxide surfaces.