NON-TECHNICAL SUMMARY: In this project, supported by the Ceramics Program in the Division of Materials Research, Professor Tewodros Asefa is developing novel nanoparticles containing defect- and strain-rich copper nanocrystals sandwiched between two metal oxides. These materials are being used to investigate the stability and catalytic activity of copper nanocrystals for the conversion of carbon dioxide (a greenhouse gas) to methanol (a synthetic fuel and a commodity chemical). While defect- and strain-rich copper nanocrystals have high catalytic activity for this chemical conversion, these very sites are also unfortunately unstable, and thus can easily lose their activity. This problem is overcome by the design of nanomaterials that comprise metal oxide cores and porous metal oxide shells around the strain- and defect-rich copper nanocrystals. This unique structure allows the nanocrystals to retain their catalytically super-active sites, while remaining stable and allowing for the systematic investigation of the interplay between the structures and catalytic properties of copper nanocrystals under high temperature (the condition used for converting carbon dioxide to methanol). State-of-the-art high-resolution neutron scattering techniques at the Center for High Resolution Neutron Scattering (CHRNS) in the National Institute of Standards and Technology (NIST) are being used to decipher the defects and strains on the nanoparticles and any changes that they may undergo during catalysis. The instrumentation at CHRNS allows for various unique characterizations of the structure and dynamics of the materials being developed. TECHNICAL DETAILS: While defect and strained sites on copper nanocrystals have been recently found to have high catalytic activity for high temperature chemical conversion of carbon dioxide to methanol, these very sites are also unfortunately thermodynamically unstable, and thus can easily undergo sintering and deactivation under these conditions. Key features of the research are the designing of core-shell nanoparticles containing stable and highly active, defect- and strain-rich copper nanocrystals sandwiched between metal oxide cores and porous metal oxide shells, and using the resulting nanocatalysts to provide a thorough understanding of the structure-property relationships of copper and other related metallic nanomaterials under high temperature catalytic conditions. The synthesis of such copper nanocrystals is carried out by a method called controlled ligand-assisted etching. The research ultimately uncovers key structural factors that need to be tailored in copper and other related metallic nanomaterials for the efficient catalysis of various reactions, including the conversion of carbon dioxide to methanol, or a greenhouse gas to a synthetic fuel or a commodity chemical. Additionally, the project provides training of a graduate student and three or more undergraduate students, including those from groups historically underrepresented in science and engineering. The students participating in this research gain interdisciplinary, hands-on training with a variety of materials synthetic methods, catalysis, and materials characterization using the infrastructure available at the Rutgers Laboratory for Surface Modification, as well as that available at NIST. Furthermore, the results from the research will be incorporated into graduate course offerings that address materials engineering for sustainable and renewable energy applications.
|Effective start/end date||7/1/15 → 6/30/18|
- National Science Foundation (National Science Foundation (NSF))