AVS 58th Annual International Symposium and Exhibition
    Surface Science Division Monday Sessions
       Session SS2-MoM

Paper SS2-MoM1
STM Dynamics Studies of Tip-Induced Reactions of Anthracene Derivatives on TiO2(110)

Monday, October 31, 2011, 8:20 am, Room 110

Session: Surface Chemical Dynamics
Presenter: Denis Potapenko, Columbia University
Authors: D.V. Potapenko, Columbia University
R.M. Osgood, Columbia University
Correspondent: Click to Email
In photocatalysis, reactions are driven by the charges that are generated in the bulk of the catalyst and then are transferred to the adsorbed molecules. Injection of electrons from the STM tip into the adsorbed molecules is a useful tool for surface dynamics studies as the energy the electrons as well as the adsorption state of the molecules could be precisely controlled. We have studied adsorption and tip-induced chemistry of anthracene and its derivatives on the TiO2(110) surface. These molecules self-assemble on the rutile(110) surface at room temperature driven by electrostatic interaction. Applying electric pulses from the STM tip to individual molecules causes desorption and in some cases dissociation as indicated by the changes in the STM images. We have observed dissociative electron capture of 2-chloroanthracene molecules that leaves behind a surface chlorine atom. The energy threshold for dissociation found as ~ 3.1 V. We report on the dynamics of this tip-induced chemistry and propose a mechanism for the observed phenomena.