7.06 - Monolayer Systems

Abstract

Monolayer metal oxide catalysts, or supported metal oxide catalysts, are ideal catalyst systems for investigating catalytic molecular/electronic structure–activity/selectivity relationships for chemical reactions. The number and nature (Brønsted acid, Lewis acid, redox, etc.) of catalytic active sites can be controlled, oxide supports can be varied, and the molecular and electronic structures of surface MOx species can readily be determined by numerous spectroscopy techniques. With modern advances in technology, it is now possible to monitor surface and bulk catalyst properties under realistic, relevant reaction conditions using operando spectroscopic techniques. Case studies from recent decades demonstrate the power of in situ and operando spectroscopy characterization at unraveling catalytic active sites and reaction mechanisms when applied to industrially important reactions such as SO2 oxidation to SO3, propane oxidative dehydrogenation to propylene, methanol dehydration to dimethyl ether, n-pentane isomerization, n-butane oxidation to maleic anhydride, and the selective catalytic reduction of NOx with NH3 to N2. New molecular level insights into these industrially important reactions from advanced in situ and operando spectroscopic characterization techniques are finally allowing scientists to tailor or molecularly engineer supported metal oxide catalysts for specific applications.