Catalytic Nanodiode

University Of Notre Dame, Notre Dame IN

Investigators

Abstract

0854324 Wolf, Eduardo E. The objective of the proposed work is to nanofabricate a catalytic diode as a model of a metal-oxide supported catalyst with the added capability to alter the electronic properties at the metal-support interface by application of an external potential. We propose to use IR spectroscopy to probe the effect of the electric field on the CO-metal surface bond. Depending on the IR results, we propose to measure the activity and selectivity as a function of applied voltage for one of two probe reactions: CO oxidation and hydrogenation of 1,3-butadiene. The catalytic nanodiode will be characterized with solid and surface analysis techniques to determine a correlation between electronic properties and catalytic activity. The novelty of the catalytic diode as a model catalyst is that it enables to study the effect of an external electrical field that has not been investigated in catalysis before. This will permit to elucidate separately the effect of electronic properties at the metal semiconductor boundary from compositional and crystallite size effects. We also propose to perform first principles molecular simulations of an analog of the junction to further understand the effect of the external field on electronic properties. The intellectual merit of this project is the investigation of a new concept of a model catalyst in which the activity of a metal-oxide interface will be altered by an external voltage. The results obtained will be the first investigation of this effect in catalysis and they will improve our understanding of the electronic effect in catalytic activity at metal-support interfaces, which although known for many years, had eluded a correlation with catalytic activity. The proposed studies will be transformative and of fundamental nature, since the model catalyst is costly to fabricate and has limited surface area. Nonetheless, we expect that the knowledge gained in these studies will permit design new improved metal catalysts supported on oxides. The results could also be relevant to other technologies involving junctions such as solar cells and solid state sensors. The broader impact of the proposed research rests upon its multi-disciplinary character including electrical engineering, advanced nanofabrication techniques, kinetics and catalysis, as well as computational chemistry. To further aid the professional growth and diverse learning experience for students of underrepresented groups, support is given for the Minority Engineering Program at Notre Dame (www.nd.edu/-mepnd) for participation in hands-on experiments. The research results will be disseminated through presentations in national meetings and publications in scientific journals in the area of catalysis, nanofabrication and computational catalysis. In addition to the existing Web pages of each investigator, a web page is under construction to publicize the work under the direction of the lead PI and collaborators in combustion synthesis in catalysis, and the work proposed here once definitive results are obtained. In addition, we propose to extrapolate what we learn about electronic effects in the nanodiode and apply it in the preparation of real metal-oxide supported catalyst. We expect that these results will bring transformative knowledge to the design of more active and selective catalysts. The fundamental insights gained in the proposed work from the combined expertise of the PI's in catalysis and co-PIs in nanofabrication and computational chemistry will benefit society in its potential use in critical technologies impacted by catalysis such as energy and in the chemical industry.