Frontiers in surface chemistry

PHYS 184

G. A. Somorjai, Somorjai@berkeley.edu, Department of Chemistry and Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720
Molecular studies of surfaces in vacuum using electron-, ion X-ray-, and molecular beam scattering revealed many of their unique properties. A large number of instruments that were developed showed that surfaces restructure when clean, and undergo further structural transformations in the presence of adsorbed atoms and molecules. The surface composition and the surface chemical bonds for specific systems were elucidated. Molecular studies at high pressures and at solid-liquid interfaces became possible using sum frequency generation (SFG) vibrational spectroscopy, scanning tunneling microscopy and other techniques. As a result, interfaces could be studied in equilibrium and many applications of surface science (catalysis, biointerfaces, electrochemistry, tribology) could be revisited on the molecular scale. Examples of investigations of catalytic reaction intermediates on metals and amino acids and peptides adsorbed on hydrophobic and hydrophilic surfaces will be described.

Metal nanoparticles with controlled size and shape, in the 1-10 nm range, are used as selective catalysts in multipath reaction studies. The unique chemical properties of nanoparticles are explored and will be discussed.