Ferroelectric PbTiO3-supported Pt films as tunable catalysts

COLL 81

Alexie M. Kolpak, kolpak@sas.upenn.edu, Ilya Grinberg, ilya2@sas.upenn.edu, and Andrew M. Rappe, rappe@sas.upenn.edu. Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104-6323
We present a novel method for dynamical control of surface structure and reactivity in oxide-supported metal catalysts. Using density functional theory, we demonstrate that switching the polarization direction of a ferroelectric PbTiO3 support can dramatically change the chemisorption energies of atoms and molecules on an ultrathin Pt(100) film. Furthermore, we show that the substrate polarization direction alters the barriers to dissociative chemisorption of CO, O2, N2, and NO. Consequently, we predict large shifts in the optimal reaction temperatures for a number of important reactions in which dissociative chemisorption of these molecules is the rate limiting step. Our results suggest exciting possibilities for external control of catalytic activity in real time.
 

Electronic Structure Modeling of Heterogeneous Catalysis
8:30 AM-12:10 PM, Monday, August 20, 2007 BCEC -- 152, Oral

Division of Colloid & Surface Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007