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Catalyst design driven by fundamental research How do we extrapolate from molecular (picoscale) and nanoscale fundamentals to operating catalytic systems? 1. Is this a worthy/practical goal? 2. What do we need to enable it? 3. Are there alternatives?
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Catalyst design driven by fundamental research How do we extrapolate from molecular (picoscale) and nanoscale fundamentals to operating catalytic systems? 1. Is this a worthy/practical goal? 2. What do we need to enable it? 3. Are there alternatives? 4. Are there fundamental differences in the way we answer these questions (and act on them) for homogeneous vs. heterogeneous catalysis?
Vision 2020 Catalyst Technology Roadmap (1997) • Primary Needs: • Enable catalyst design through combined experimental and mechanistic understanding, and improved computational chemistry. • 2. Development of techniques for high throughput synthesis of catalysts and clever new assays for rapid throughput catalyst testing, potential combinatorial techniques, and reduction of analytical cycle time by parallel operation and automation. • 3. Better in situ techniques for catalyst characterization • 4. Synthesis of catalysts with specific site architecture
Catalyst design = ability to specify and synthesize catalysts to achieve desirable chemical transformations Translate molecular (picoscale) and nanoscale fundamentals to catalyst design at this length scale “Catalyst design driven by fundamental research is the exception rather than the norm.”
Examples of success in catalyst design driven by fundamental research From understanding known catalysts to inventing new ones: • Translating understanding of ceria function in 3-way exhaust catalysts into new water-gas-shift catalysts • New supported oxide monolayer catalysts for alcohol oxidation • Selective catalytic oxidation of benzene to phenol using nitrous oxide
Examples of success in catalyst design driven by fundamental research • Ligand design in homogeneous catalysis: • Single Site olefin polymerization catalysts • Enzyme analogs: synthetic di-iron complexes that mimic hydrogenases
Examples of success in catalyst design driven by fundamental research • Catalyst design from first principles – Theory and Experiment: • Gold-Nickel steam reforming catalyst • Bimetallic ammonia synthesis catalyst • Oxide catalysts for selective ketene synthesis
CentralThemes and Concepts:Key characteristics of successes • Recognition of reactivity patterns • Close interaction of theory and experiment • Synthesis and testing of designs • Multidisciplinary approaches/ multidisciplinary collaborations
Critical needs • Better understanding of molecular level mechanisms • Better access to synthetic capabilities • Better ways of creating models of working catalysts • Better understanding of attributes that make for successful scale-up • (Better communication/collaboration) • Fundamental studies of the thermodynamics of bonds • “Catalysis Informatics” • Materials structure of complex systems: from atom connectivity to physical, chemical and electronic properties • New ligand platforms • New supports • New reaction environments • (Dynamics of elementary processes)
Goals, Challenges and Opportunities Vision 2020 technology targets remain relevant Selective oxidation Alkane activation Byproduct and waste minimization Stereoselective synthesis Functional olefin polymerization Alkylation Living polymerization Alterative feedstocks and renewables Additions to this list Photocatalytic water splitting Low cost oxidants NO decomposition Methane conversion to useful products Clean transportation fuels Fuel cells Replacement of Pt-group metals New materials that embody nanoscale control of structure and chemical function Catalysis from first principles offers a fresh approach to these challenges
Frontiers in Chemical Engineering (1988) “With sufficient development of theoretical methods, it should be possible to predict the desired catalyst composition and structure to catalyze specific reactions prior to formulation and testing of new catalysts.”
Opportunities in Chemistry (1985) “We propose an initiative to apply the techniques of chemistry to obtain a molecular-level and coherent understanding of catalysis that encompasses heterogeneous, homogeneous, photo-, electro-, and artificial enzyme catalysis.”