Fundamental Catalysis Science in the DOE/Office of Basic Energy Sciences Chuck Peden, Laboratory Fellow, Emeritus Pacific Northwest National Laboratory • DOE, Office of Science and BES Structure • About the BES Catalysis Science Program • Some current and future challenges and opportunities for the BES CS Program • Some examples of specific relevance to emission control catalysis interspersed in the discussion Disclaimer: The opinions presented are those of the presenter and do not necessarily reflect those of the U.S. Department of Energy or Pacific Northwest National Laboratory. Only publicly available information is being shared.
Transcript
Fundamental Catalysis Sciencein the DOE/Office of Basic Energy Sciences
Chuck Peden, Laboratory Fellow, EmeritusPacific Northwest National Laboratory
• DOE, Office of Science and BES Structure• About the BES Catalysis Science Program• Some current and future challenges and
opportunities for the BES CS Program• Some examples of specific relevance to emission
control catalysis interspersed in the discussion
Disclaimer: The opinions presented are those of the presenter and do not necessarily reflect those of the U.S. Department of Energy or Pacific Northwest National Laboratory. Only publicly available information is being shared.
SecretaryRick Perry
$34.5 B FY2018
Department of Energy
Federal EnergyRegulatory
Commission
Under Secretary for Nuclear Security/ Administrator for
Nuclear Security
Dep. Administrator for Defense Programs
Dep. Administrator for Defense Nuclear Nonproliferation
Dep. Administrator for Naval Reactors
Director,Office of Science
$6.3 B
Assistant Secretary for Fossil Energy $727 M
Assistant Secretary for Energy Efficiency and
Renewable Energy$2.3 B
Assistant Secretary for Environmental Management
$7.1 B
Office of Security and Emergency Operations
Chief Information OfficerOffice of Independent Oversight
and Performance AssuranceOffice of Public AffairsOffice of PolicyOffice of Management
and AdministrationOffice of Worker and
Community TransitionOffice of Hearings and AppealsContract Reform and
• Bioenergy Technologies (biomass conversion)• Stable catalysts in water
• Office of Fossil Energy• Coal liquefaction• CO2 capture and conversion
• Catalytic CO2 reduction
• Natural gas (methane) conversion• C-H activation
Relevance of BES/Catalysis Science to DOE Mission Agencies
High‐Surface‐Area Ceria by Atomic Layer Deposition on Al2O3
Scientific AchievementConformal, 0.5-nm films of CeO2 were prepared on anAl2O3 support by ALD. The CeO2/Al2O3 catalyst hasidentical catalytic properties to bulk CeO2; but, unlikebulk CeO2, the ALD sample maintains its surface areaand activity after high temperature treatment.
Significance and ImpactCeria is used in three-way auto catalysts and is apromoter in many important reactions, such as water-gas shift (WGS). However, it loses surface area andredox activity under operation. By forming a thinconformal film on Al2O3, surface area and activity aremaintained.
Research Details• A uniform CeO2 film (28-wt%, 0.5-nm thick) was
grown on 130-m2/g Al2O3.• Pd/CeO2/Al2O3 prepared by ALD showed high activity
for WGS and was completely stable upon heating to900°C, while bulk Pd/CeO2 and Pd/CeO2/Al2O3prepared by infiltration were unstable.
• The method is completely general for forming high-surface-area, functional supports.
TEM of Pd/CeO2/Al2O3 prepared by ALD (a) and by impregnation (b), showing the very different structure.
Diagram of the CeO2/Al2O3structures.
CO oxidation rates showing that the of Pd/CeO2/Al2O3 catalyst prepared by ALD exhibits superior stability and performance.
Work was performed at the University of Pennsylvaniaand the University of Michigan.
T. Z. Onn, S. Zhang, L. Arroyo‐Ramirez, Y. Xia, C. Wang, X. Pan, G. W. Graham, and R. J. Gorte, Applied Catalysis B 201 (2017) 430‐437.
Strategic Planning – The Role of PI Meetings
Date of Conference Title of Conference
June 22‐June 24, 2016 Science of Catalytic Reaction Mechanisms
July 19‐July 22, 2015 Benchmarking Catalysis Science
July 20‐July 23, 2014 Frontiers at the Interface of Heterogeneous and HomogeneousCatalysis, II
June 30‐July 2, 2013 Frontiers at the Interface of Heterogeneous and Homogeneous Catalysis
October 2‐5, 2011 Frontiers in Catalysis: Heterogeneous, Surface, Photo‐ and Electrochemical
June 1‐4, 2010 Organometallic and Bioinspired Catalysis Science
May 31‐June 3, 2009 Advanced Synthesis, Characterization, and Modeling
May 18‐21, 2008 Molecular Catalysis Science
May 23‐26, 2007 Interfacial and Nano Catalysis
May 21‐24, 2006 Organometallic, Inorganic, and Bioinspired Chemistry and Catalysis
Informing Current Catalysis Program Strategic Directions
NAS Review of the BES Catalysis Science Program - 2009
Modest changes in portfolio were recommended, consistent with the strategic planning put forward at that time:
Basic Research Needs: Catalysis for Energy - 2007 Grand challenges for catalysis science
Understanding the mechanisms and dynamics of catalyzed reactions at the atomic and molecular scale.Design and controlled synthesis of catalyst structures.
Priority Research Directions:Understanding complex transformations of fossil fuel feedstocksUnderstanding lignocellulosic biomass and the chemistries of deconstructionUnderstanding the chemistry for conversion of biomass-derived oxygenates to fuelsPhoto- and electrochemical conversion of H2O and CO2
Current Strengths Recommendations
Heterogeneous Catalysis
Surface science; nanoscale catalysis; theory
Catalyst design; new synthesismethods; unique reactor systems; new characterization tools; new chemical reactions
Homogeneous Catalysis
Single‐site polymerization, C‐H activation and functionalization, and organic synthesis
C‐H bond functionalization; new approaches to transition metal catalysis and electrochemical catalysis; catalysis for bioderivedmaterials into fuels, bioinspired catalytic processes
Experimental and Theoretical Insights into the Hydrogen‐Efficient Direct Hydrodeoxygenation Mechanism of Phenol over Ru/TiO2
Scientific AchievementBased on experimental and theoretical evidence a newmechanism for direct deoxygenation of phenoliccompounds at the metal/oxide interface wasproposed. This mechanism involves heterolytic H2cleavage to form an interfacial Brønsted acid site.
Significance and ImpactIn contrast to prior studies, this work emphasizes theamphoteric nature of TiO2, rather than its reducibility,as key requirement for selective deoxygenationcatalysts.
Research Details– Isotopic labeling experiments and TEM data areconsistent with direct deoxygenation, not withhydrogenation pathways, for small Ru particle sizes.– Density functional theory (DFT) calculationseliminate hydrogen spillover for support reduction.– Computational modeling suggests that the interplaybetween metal and acid sites to create a bifunctionalenvironment is paramount for efficient C‐O cleavage.
Work was performed at Bates College,U of Houston, and U of Maine, Orono.
R. C. Nelson, B. Baek, P. Ruiz, B. Goundie, A. Brooks, M. C. Wheeler, B. G. Frederick, L. C. Grabow, R. N. Austin, ACS Catal. 5 (2015), 6509–6523.
(A) Heterolytic H2 dissociation at the Ru/TiO2 interface creates a support water molecule with Brønsted acid character.(B) We propose the that balanced acid/base properties of the amphoteric TiO2 support are largely responsible for selective, direct cleavage of the C‐O bond in phenol.
A
B
Ru
Support Ti TiO
HH H
Ru
Support Ti TiO
H
H H Ru
Support Ti TiO
H
H HO
H
Basicity Acidity
OH H2
Informing Current Catalysis Program Strategic Directions
NAS Review of the BES Catalysis Science Program - 2009
Modest changes in portfolio were recommended, consistent with the strategic planning put forward at that time:
Basic Research Needs: Catalysis for Energy - 2007 Grand challenges for catalysis science
Understanding the mechanisms and dynamics of catalyzed reactions at the atomic and molecular scale.Design and controlled synthesis of catalyst structures.
Priority Research Directions:Understanding complex transformations of fossil fuel feedstocksUnderstanding lignocellulosic biomass and the chemistries of deconstructionUnderstanding the chemistry for conversion of biomass-derived oxygenates to fuelsPhoto- and electrochemical conversion of H2O and CO2
16
Current Strengths Recommendations
Heterogeneous Catalysis
Surface science; nanoscale catalysis; theory
Catalyst design; new synthesismethods; unique reactor systems; new characterization tools; new chemical reactions
Homogeneous Catalysis
Single‐site polymerization, C‐H activation and functionalization, and organic synthesis
C‐H bond functionalization; new approaches to transition metal catalysis and electrochemical catalysis; catalysis for bioderivedmaterials into fuels, bioinspired catalytic processes
Probing a Chemical Bonding Being Born CO + O → CO2 on Ru catalyst
H. Öström, H. Öberg, H. Xin, J. LaRue, M. Beye, M. Dell’Angela, J. Gladh, M. L. Ng, J. A. Sellberg, S. Kaya, G. Mercurio, D. Nordlund, M. Hantschmann, F. Hieke, D. Kühn, W. F. Schlotter, G. L. Dakovski, J. J. Turner, M. P. Minitti, A. Mitra, S. P. Moeller, A. Föhlisch, M. Wolf, W. Wurth, M. Persson, J. K. Nørskov, F. Abild‐Pedersen, H. Ogasawara, L. G. M. Pettersson, A. Nilsson, Science, 347, 978‐982 (2015).
Scientific AchievementUltrafast time resolved X‐ray absorption spectroscopy (XAS) probed the electronic structure during chemicalbond formation.
Significance and ImpactFirst experimental observation of spectra close to transition state for surface chemical reaction. Confirmation of theoretical description of bond formation and, hence, description of surface catalysis
Research Details‐ X‐ray FEL followed the state‐to‐state transition initiate by 400 nm laser pulse.‐ DFT calculations show transient signatures in XAS are assignable tospecies near the transition states.‐ Short lived O‐CO species are identified along the reaction coordinate.
Changes in Our Energy Landscape Drive the Need for Advances in Catalysis
Quad = 1015 BTU; 2007 consumption ≈ 2015 consumption LLNL flowcharts available from https://flowcharts.llnl.gov
Catalysis(chemical
production)Catalysis (feedstocks to
energy carriers)
Chemical Energy Carriers
Electrical Energy Carriers
Energy Resources
Energy Carriers
Energy Services
% Contribution2007 20150.1 0.5
8.7 8.6
0.9 2.5
0.1 1.9
0.4 0.2
22 29
23 16
3.0 4.8
41 36
Carl Koval ‐ Presentation to BESAC, July 2017
Impact of New Energy Technologies on the US Chemical Industry
americanchemistry.com/Policy/Energy/Shale-Gas
Carl Koval ‐ Presentation to BESAC, July 2017
New Paradigms in Catalysis Science
Metal-free redox catalysis using Frustrated Lewis Pairs
Room temperature H2 activation leads to hydrogenation of unsaturated organic compounds..
Stabilization of isolated metal atoms on oxide supports
Individual Pt atoms (bright dots) are stabilized on the surface of CeO2and catalyze CO oxidation without sintering.
Outer coordination sphere assistance in multiproton,
multielectron reactions
The rate of electrochemical H2evolution is dramatically enhanced by strategic placement of pendant amines that function as proton relays to a metal hydride.
Carl Koval ‐ Presentation to BESAC, July 2017
Stephan, Acc. Chem. Res.2015, 48, 306-316
Datye et al., Science2016, 353, 150-154.
Bullock et al., Chem. Commun.2014, 50, 3125-3143.
• Methanol‐to‐olefins technology has emerged (from a 50‐year‐old discovery) as one of the leading technologies for dedicated light olefin synthesis (>20 new plants worldwide)
• Fundamental science was indispensable for targeted catalyst development
Dedicated Olefin Synthesis from Methanol
Aromatic cycle Olefin cycle
CH3OH
H2O
CH3OH
H2O
CH3OH
H2O
H2O
CH3OH
H2O
CH3OH
CH3OH
H2O
H2O
CH3OH
H2O
CH3OH
CH3OH
Olefins,AromaticsWater
Translation
Inspiration
Patience et al., Chem. Eng. Sci. 2007, 62, 5527.
Carl Koval ‐ Presentation to BESAC, July 2017
Low Temperature Catalysts for Diesel Exhaust Aftertreatment
Fuel-efficient diesel vehicles created new challenges for catalysis. Starting in 2007, NOx had to be removed from exhaust gases to meet stricter air quality standards. In selective catalytic reduction (SCR), a Cu/zeolite catalyst uses NH3 to reduce NOx to N2.
Bifunctional Cu/chabazitecatalyst, selective for SCR and resistant to poisoning
due to Cu2+ confinement in small zeolite pores
www.basf.com
Ford DOC-SCR-DPF system layout - Beale, Peden et al., Chem. Soc. Rev. 2015, 44, 7371
McEwen, Peden et al., ACS Catal. 2014, 4, 4093
Carl Koval ‐ Presentation to BESAC, July 2017
Mechanisms and dynamicsControlled catalyst synthesisHeavy fossil energy feedstocksBiologically derived feedstocksConversion of CO2 and H2O
New Catalysis Science to Transform Energy Technologies
Panel 1: Diversified Energy Feedstocks and CarriersPanel 2: Novel Approaches to Energy TransformationsPanel 3: Advanced Chemical Conversion ApproachesPanel 4: Cross-cutting Capabilities and Challenges in
Synthesis, Characterization, Theory and Computation
From feedstock focus to understanding and using chemical complexity.
Susannah ScottUC Santa Barbara
Johannes LercherPacific Northwest National Lab Technical University Munich
Carl KovalUniversity of Colorado, Boulder
BRN 2007 BRN 2017
Carl Koval ‐ Presentation to BESAC, July 2017
The significant changes just described drove the need for a new Basic Research Needs Workshop in Catalysis Science.
Plenary Presentations at 2017 BRN Workshop
Catalyst Design for Sustainable Production of Fuels and Chemicals Jens Norskov (Stanford)
The Nexus of Reaction Mechanism and Dynamic Materials Properties in Designing Catalytic Processes Cynthia Friend (Harvard)
Opportunities for Catalysis in Utilization of Biomass Resources Jim Dumesic (Wisconsin)
Creating New Economic Advantages from US Oil and Gas Jim Rekoske (UOP)
Lessons From the Quest for Cellulosic Biofuels…… Kim Johnson (Shell)
Frontiers, Challenges and Opportunities in Biological and Bio-Inspired Catalysis Russ Hille (UC Riverside)
Impact of Catalytic Technology on Use of Renewable Energy Resources Reuben Sarkar (EERE)
Carl Koval ‐ Presentation to BESAC, July 2017
Plenary Presentations at 2017 BRN Workshop
Catalyst Design for Sustainable Production of Fuels and Chemicals Jens Norskov (Stanford)
The Nexus of Reaction Mechanism and Dynamic Materials Properties in Designing Catalytic Processes Cynthia Friend (Harvard)
Opportunities for Catalysis in Utilization of Biomass Resources Jim Dumesic (Wisconsin)
Creating New Economic Advantages from US Oil and Gas Jim Rekoske (UOP)
Lessons From the Quest for Cellulosic Biofuels…… Kim Johnson (Shell)
Frontiers, Challenges and Opportunities in Biological and Bio-Inspired Catalysis Russ Hille (UC Riverside)
Impact of Catalytic Technology on Use of Renewable Energy Resources Reuben Sarkar (EERE)
Carl Koval ‐ Presentation to BESAC, July 2017
Panel Breakout Sessions at 2017 BRN Workshop
Panel 1: Diversified Energy Feedstocks and CarriersGeoffrey Coates, Cornell University Enrique Iglesia, University of California Berkeley, and LBNL
Panel 2: Novel Approaches to Energy TransformationsMorris Bullock, Pacific Northwest National Laboratory Thomas Jaramillo, Stanford University, and SUNCAT/SLAC
Panel 3: Advanced Chemical Conversion Approaches Maria Flytzani-Stephanopoulos, Tufts UniversityCathy Tway, Dow Chemical CompanyDaniel Resasco, University of Oklahoma
Panel 4: Crosscutting Capabilities and Challenges: Synthesis, Theory, and Characterization
Karena Chapman, Argonne National LaboratoryVictor Batista, Yale UniversitySheng Dai, Oak Ridge National Laboratory
Carl Koval ‐ Presentation to BESAC, July 2017
Panel Breakout Sessions at 2017 BRN Workshop
Panel 1: Diversified Energy Feedstocks and CarriersGeoffrey Coates, Cornell University Enrique Iglesia, University of California Berkeley, and LBNL
Panel 2: Novel Approaches to Energy TransformationsMorris Bullock, Pacific Northwest National Laboratory Thomas Jaramillo, Stanford University, and SUNCAT/SLAC
Panel 3: Advanced Chemical Conversion Approaches Maria Flytzani-Stephanopoulos, Tufts UniversityCathy Tway, Dow Chemical CompanyDaniel Resasco, University of Oklahoma
Panel 4: Crosscutting Capabilities and Challenges: Synthesis, Theory, and Characterization
Karena Chapman, Argonne National LaboratoryVictor Batista, Yale UniversitySheng Dai, Oak Ridge National Laboratory
Carl Koval ‐ Presentation to BESAC, July 2017
Primary outcome of the workshop is a list of “Priority Research Directions”
Priority Research Direction 1Construct catalyst architectures to incorporate strong and weak interactions that organize matter and space beyond the binding siteThe extended structure of the active site includes not only the locations where the molecular orbitals of the reactants interact directly with the catalyst, but also nearby regions in space where the atomic organization in 3-dimensions serves to assemble and precisely position both reacting molecules and non-reacting components such as solvent molecules and counter-ions to achieve selective chemical transformations at high rates.
Fu et al. Proc. Natl. Acad. Sci. 2017, 114, 5930. Scott et al. ACS Catal. 2017, 114, 5930.
Metal nanoparticle catalyst confinement, (A) inside a zeolite pore; (B) inside a carbon nanotube; (C) beneath a graphene sheet
Glucose solvation by water in a zeolite supercage
Carl Koval ‐ Presentation to BESAC, July 2017
Constructing Cooperative Catalyst Architectures
o How do we map the cooperative roles in catalyst-substrate ensembles at an atomistic level, using powerful emerging characterization and theory methods?
o How do we design synthesis methods that direct the organization of structural and functional motifs in the extended catalyst architecture so as to influence the ground and transition states of reacting molecules?
Davis et al., ACS Catal. 2015, 5, 5679Iglesia et al., J. Catal. 2016, 344, 817.
Chirik et al., Science 2015, 349, 960.Effect of metal-acid site proximity on activity and
selectivity in bifunctional catalysts
Carl Koval ‐ Presentation to BESAC, July 2017
Control the dynamic evolution of catalysts by influencing the rates and directing the pathways for reorganization
Priority Research Direction 2
Catalysts are inherently dynamic materials whose local and extended structures change continuously, beginning when the components are assembled into a catalytically active architecture and continuing as materials interact with reaction mixtures.
TiOx bilayer on Pdnanoparticle under reducing conditions
TiOx monolayer on Pdnanoparticle under
H2/O2 mixture
No TiOx layer on Pdnanoparticle under oxidizing conditions
Pd
TiO2
TiOx TiOxPdPd
Pan et al. Nano Lett., 2016, 16, 4528-4534.
Carl Koval ‐ Presentation to BESAC, July 2017
Observing and Directing Complex Catalyst Behavior
Kooyman, Helveg, et al. Nature Mater., 2014, 13, 884-890.
Time-resolved TEM images of Pt nanoparticle exposed to CO/O2 at 727 K
o How do we monitor changes in catalysts in real time and relate their consequences to reactivity and selectivity?
o How do we design catalysts to control their rates of activation, deactivation, and reactivation?
Grunwaldt et al. J. Phys. Chem. C, 2009, 113, 3037.
Reduction/ignition of individual Pt-Rh nanoparticles during catalytic partial
oxidation of methane
Carl Koval ‐ Presentation to BESAC, July 2017
Decode complex networks of reactions, and integrate catalytic reactions with molecular transport and separations
Priority Research Direction 3
Emerging chemical fuels and feedstocks are often mixtures that present challenges for catalysis in terms of their inherent complexity and variability. In addition, their highly distributed nature will require entirely new approaches to catalytic processing.
Alternative feedstocks have huge energy potential, and pose unique challenges for catalyst technology.
Integration of Reaction with Separation and Design for Catalyst Resilience
o How do we design catalysts that adapt to transients in feed composition and reaction conditions, and that are capable of operating in highly distributed systems with minimal external control?
Cronin et al. Chem. Sci. 2013, 4, 3099.
Self-healing oxygen-evolving catalyst
Nocera et al. J. Am. Chem. Soc. 2009, 131, 3838.
Achieving spatial control over catalysts, reactions and separations
Carl Koval ‐ Presentation to BESAC, July 2017
Priority Research Direction 4Design electrocatalyst systems to optimize electron-driven processes for precise chemical transformations efficiently under mild conditions
The interconversion of chemical and electrical energy is based on the ability to store energy in chemical bonds and retrieve energy from those bonds by using the electron potential to control the directions and rates of chemical processes.
Electrochemical systems offer the possibility to drive chemical transformations under mild conditions, where thermal catalysis is inefficient.
Carl Koval ‐ Presentation to BESAC, July 2017
Enhancing Activity in Molecular Electrocatalysts for H2 Production
o How do we design conducting solid/solution interfaces, and coupled redox reaction chemistries, that catalyze electron-driven chemical processes with high precision and efficiency under mild conditions?
o How do we improve electrocatalysts for critical multi-electron, multi-proton reactions, and also expand the repertoire of chemical transformations that can occur effectively in electrochemical systems?
o How do we develop new electrocatalytic systems that circumvent known scaling relationships through detailed mechanistic understanding of catalytic pathways?
Carl Koval ‐ Presentation to BESAC, July 2017
MoS2 nanoparticles
Core-shell MoO3-MoS2 nanowires
Mesoporous MoS2 thin films
[Mo3S13]2- clusters
3
2
1
Jaramillo, Besenbacher et al., Nat. Chem., 2014, 6, 248.
HER activity in 0.5 M H2SO4
Priority Research Direction 5Drive new catalyst discoveries using data science to resolve complex structure-function relations, predict new catalyst properties, and design more incisive experimentsThe complex coupling of many variables that govern catalyst reactivity and its evolution in time makes it challenging to discern relationships between catalyst structure/composition and performance.
High dimensional screening of catalysts for selective oxidation of propene to acrolein
Rajan et al. J. Comb. Chem. 2009, 11, 385Milo, Neel et al. Science 2015, 347, 6223
Multivariate analysis of catalytic C-N bond formation
Carl Koval ‐ Presentation to BESAC, July 2017
Mining Complex Information Using Data Science Approacheso How do we deploy the tools of machine learning to find and extract robust, often
unexpected structure-activity relations from large, heterogeneous datasets? o How do we use this information to predict effective combinations of catalytic
structural components and reaction cascades, leading to entirely new catalyst formulations?
Bligaard, Nørskov, et al. Nat. Commun.2017, 8, 14621
Machine learning simplifies reaction network for syngas (CO+H2) conversion to acetaldehyde over Rh(111)
In situ multimodal 3D chemical imaging of a hierarchically structured core@shellcatalyst for methanol synthesis
Grunwaldt et al. J. Am. Chem. Soc. 2017, 139, 7855
Carl Koval ‐ Presentation to BESAC, July 2017
As-prepared catalyst Active catalyst Dynamic catalyst behavior Controlled catalystarchitecture and performance
Unsupervisedlearning
Theo
ry a
nd
com
puta
tiona
l m
odel
ing
Correlativelearning
Image recognition
In-situ controlData science:
Syn
thes
is, a
tom
ican
d m
esos
cale
ch
arac
teriz
atio
n
Electronic structure Multiscale modelingAb initio dynamics
after Olga Ovchinnikova, ORNL
o How do we use data science tools to design better experiments with higher resolution and greater sensitivity, and extract more information from them?
Extracting More Detailed Information from Experiments
Molecular dynamics simulations
Carl Koval ‐ Presentation to BESAC, July 2017
Concluding Remarks
• The BES Catalysis Science (BES/CS) Program is the largest U.S. funder of fundamental catalysis science.
• There are a number of examples of prior funded BES/CS research that has advanced catalytic vehicle emission control technologies.
• Recent Basic Research Needs Workshop on Catalysis is informing the future directions of the BES/CS program:
– Low‐temperature catalysis– Novel catalysis by isolated, oxide‐supported single‐metal atoms– Accounting for ‘weak’ as well as ‘strong’ interactions in catalysis; e.g., ‘confinement’ effects in the nano‐spaces of zeolites
– Use the nascent area of ‘data science’ and ‘machine‐learning’ to utilize greatly expanding amounts of data for understanding and controlling catalytic processes.
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