Infrared Absorption Spectroscopy of Adsorbed CO: New Applications in Nanocatalysis for an Old Approach

摘要

In this minireview, the power of using a well-established approach, CO infrared absorption spectroscopy, as a probe for the characterization of novel nanostructured catalysts is discussed. It is argued that the peak positions of the C?O stretching mode in IR spectra can be used not only to differentiate between adsorption on metals catalysts and oxide supports, but also to provide information on the oxidation state of the metal, on the surface planes available for adsorption, and on the adsorption bonding modes possible. Perhaps more basic but more important for nanocatalysis applications is the usefulness of the information provided by CO IR spectroscopy to identify and quantify the sites accessible to reactants in the catalytic surfaces of complex nanoarchitectures. A number of examples are provided here from studies by our group to illustrate these points, including the characterization of catalysts based on dendrimer- and mesoporous-silica-encapsulated metal nanoparticles and on core@shell and yolk@shell nanostructures.