Using scanning tunneling microscopy and density functional theory simulations, a

study was made of the diffusion of alkoxy species formed by the dissociation of

alcohols on bridge-bonded oxygen vacancies on TiO2(110). At above 400K, the

sequential isothermal scanning tunneling microscopic images showed that mobile

bridge-bonded oxygen vacancies mediate the diffusion of alkoxy species by

providing space for alkyl-group-bearing bridge-bonded oxygen atom to diffuse

into. The experimental findings were further supported by simulations that find that

bridge-bonded oxygen vacancy diffusion was the rate-limiting step in the overall

diffusion mechanism.

Vacancy-Assisted Diffusion of Alkoxy Species on Rutile TiO2(110). Z.Zhang,

R.Rousseau, J.Gong, S.C.Li, B.D.Kay, Q.Ge, Z.Dohnálek: Physical Review

Letters, 2008, 101[15], 156103