Joseph H. Holles, Michigan Technological University
April 13, 2010
11:00 AM - 12:00 PM
Catalyst Design Using Pseudomorphic Overlayers
Abstract:
Supported metal catalysts have been the mainstay of the chemical industry for many years. In order to improve the activity of these catalysts, the researcher may change the metal, particle size, support, add dopants or promoters, or even combine metals. All of these approaches serve to change the electronic interaction between the catalyst and the reactants and products. Historically, this catalyst development was done by trial and error similar to the medieval alchemist. Today, we can computationally predict in advance this important electronic interaction using first principles quantum chemical techniques. In particular, the pseudomorphic overlayer of a monolayer of one metal on the bulk structure of another metal has shown tremendous promise for systematically controlling the electronic interaction. However, to date, this work has been limited to computational or single crystal high vacuum studies.
We have developed a synthesis technique to move this catalyst structure into the real world of high surface-area supported catalysts. The directed deposition synthesis technique allows for the controlled deposition of no more than one layer of metal on previously deposited particles of a different metal. A series of Re@Pd (core@shell) catalysts have been synthesized using the directed deposition technique. These catalysts were then characterized using hydrogen chemisorption to determine binding energy and ethylene hydrogenation to determine activity.
Date posted
Jun 17, 2019
Date updated
Jun 17, 2019