In Situ Nanocharacterization of the Synthesis and Early Evolution of Supported Metal and Bimetallic Nanoparticles for Catalytic Applications

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AbstractProposal Title: GOALI: In Situ Nanocharacterization of the Synthesis and Early Evolution of Supported Metal and Bimetallic Nanoparticles for Catalytic Applications Proposal Number: CTS-0553445Principal Investigator: Peter A. CrozierInstitution: Arizona State UniversityAnalysis (rationale for decision):The goal of this research is to develop a fundamental understanding of the nanoscale processes that take place during the synthesis and early operation of supported metal catalysts. The technological impacts of supported metal catalysts on society are enormous, and there are many important scientific questions that remain unanswered concerning their synthesis and operation under reactive gas conditions. In the synthesis of many supported metal catalysts, self-assembly processes create fine dispersions of metal nanoparticles on high surface area supports. This research will investigate the steps in these self-assembly processes and also the evolution of catalyst morphology under near reactor conditions. The unique capabilities of a state-of-the-art in situ environmental electron microscope will allow the dynamic nanoscale changes to be directly observed on high surface area supports. The role of nanoscale surface support features (such as steps, edge sites, surface facets and point defects) on the metal precursor distribution, decomposition, diffusion and subsequent nanoparticle nucleation and growth will be studied. The research will focus on metal particles synthesized using solution impregnation techniques because this approach is widely used for the synthesis of industrial catalysts. Experiments will also be undertaken to correlate the nanoscale chemical and morphological changes that take place on the metal nanoparticles under near reactor conditions. The nanostructural changes will be correlated with catalytic properties for two relatively simple reactions of relevance to energy production: partial oxidation of methane and the water-gas shift reaction.The broader technological impact of the proposed work will be significant because the information obtained from this research can be used to develop improved methods for controlling nanoparticle formation and evolution of supported metal catalysts. The impregnation techniques to be examined in this project are widely used for manufacturing commercial catalysts. Correlating the nanoscale changes that take place during gas-solid reactions with catalyst performance will contribute to a molecular-level understanding of the synthesis-structure-performance relationships. Several broader educational objectives will be addressed by the proposed research. Graduate and undergraduate students and a postdoctoral fellow will be trained in understanding and mastering modern methods of synthesis, materials nanocharacterization and catalyst characterization. Summer intern positions will be offered to outstanding high school students from traditionally underrepresented groups. The direct involvement of industry research scientists in this program will provide the students with an excellent perspective on the relationship between basic research and technology development. The research results will be quickly disseminated to the GOALI partner and the knowledge gained through this research program will also be transferred to other industrial companies through an Industrial Associates Program at the Center for Solid State Science.