Nanoscale chlorine induced restructuring of Au(111)

CATL 13

Weiwei Gao, wgao@fas.harvard.edu1, Dilini S. Pinnaduwage, pinnaduw@fas.harvard.edu2, Ling Zhou2, Robert J. Madix2, and Cynthia M. Friend1. (1) Department of Chemistry & Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, (2) School of Engineering and Applied Sciences, Harvard University, 27 Oxford Street, Cambridge, MA 02138
Motivated by the dramatic chlorine promotion effect on gold-catalyzed partial oxidation, we study chlorine-gold interaction on Au(111) by using scanning tunneling microscopy (STM) combined with temperature programmed desorption (TPD), low energy electron diffraction (LEED) and X-ray photoelectron spectroscopy. On clean Au(111), chlorine exhibits complex desorption behavior at different coverages according to TPD experiments. LEED and STM further reveal that chlorine interaction with gold involves incorporation of gold atoms to form surface compound of different structures. When chlorine interacts with Au-O complex, STM visualizes the dispersal and redistribution of nanoscale Au islands stabilized by oxygen on the surface. The oxygen spatial organization change upon interaction with chlorine is used to explain one of the major mechanisms for chlorine promotion of olefin oxidation by Au.
 

Nanotechnology in Catalysis V
1:30 PM-4:50 PM, Sunday, August 19, 2007 BCEC -- 261, Oral

Catalysis & Surface Science Secretariat

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