Israel Wachs

G. Whitney Snyder Professor and Professor of Chemical Engineering
Director, Operando Molecular Spectroscopy and Catalysis Research Lab

Ph.D. Stanford University, 1977
M.S. Stanford University, 1974
B.E. City College of New York, 1973

Contact Information
phone: (610) 758-4274
fax: (610) 758-5057

Our research focuses on surface oxides and has demonstrated that, for many two-component metal oxide systems, one metal oxide may be present as an atomically dispersed phase over a second metal oxide substrate. The state of the atomically dispersed metal oxide, the surface oxide, has a different structure from that of its bulk unsupported oxide counterpart. This structural difference usually results in very different chemical properties. Our studies have shown that a relationship exists between the metal oxide structure and its surface reactivity (reduction properties and catalytic activity or selectivity).

The complex structures of the atomically dispersed surface oxides are poorly understood. The focus of our program is therefore to examine systematically the various structures of these atomically dispersed surface oxides on oxide substrates and to determine the factors that control the metal oxide structure. Much of the structural information about surface oxides can be provided with modern laser Raman spectroscopy because of the dependence of the Raman spectrum on the structure of the scattering material.

Another of our goals is to define the relationship between surface oxide structures and their various physical and chemical properties. A better understanding of the synthesis and materials science/solid-state chemistry of the surface oxides is also emerging from this research program. The insight generated from this research has implications for metal oxide catalysts, ceramic materials, pigment materials, and electronic devices which find wide application in the pollution control industry, chemical industry, petroleum industry and the advanced materials industries.