AVS 57th International Symposium & Exhibition
    Surface Science Friday Sessions
       Session SS-FrM

Paper SS-FrM8
Hydrogen Bonding Controls the Dynamics of Catechol Adsorbed on a TiO2(110) Surface

Friday, October 22, 2010, 10:40 am, Room Santa Ana

Session: Reactivity of Oxides, Mainly TiO2
Presenter: S.-C. Li, Tulane University
Authors: S.-C. Li, Tulane University
L.-N. Chu, East China University of Science and Technology, China
X.-Q. Gong, East China University of Science and Technology, China
U. Diebold, Tulane University and Vienna University of Technology, Austria
Correspondent: Click to Email
Direct studies of how organic molecules diffuse on metal oxide surfaces can provide insights into catalysis and molecular assembly processes. We studied individual catechol molecules, C6H4(OH)2, on a rutile TiO2(110) surface with scanning tunneling microscopy (STM). Surface hydroxyls enhanced the diffusivity of adsorbed catechol ates . The capture and release of a proton caused individual molecules to switch between ‘mobile’ and ‘immobile’ states within a measurement period of minutes. Density functional theory (DFT) calculations show that the transfer of H from surface hydroxyls to the molecule and its interaction with surface hydroxyls substantially lowered the activation barrier for rotational motion across the surface. Hydrogen bonding can play an essential role in the initial stages of the dynamics of molecular assembly.