Past Seminars & Events

Professor Kenneth Hanson

Department of Chemistry & Biochemistry

Florida State University

Abstract

Harnessing Molecular Photon Upconversion Using Self-Assembled Multilayers on Metal Oxide Surfaces

Photon upconversion—combining two or more low energy photons to generate a higher energy excited state—is an intriguing strategy for increasing the maximum theoretical solar cell efficiencies from 33% to greater than 43%. In this presentation we will recount our work using self-assembled multilayers of sensitizer and acceptor molecules on nanocrystalline metal oxide films as a unique structural motif for facilitating molecular photon upconversion via triplet-triplet annihilation (TTA-UC) and directly extracting charge from the upconverted state. Under light intensities as low as ambient solar flux we demonstrate a more than four-fold increase in the short circuit current relative to the sum of the sensitizer and acceptor monolayer devices. We will discuss the dynamics events during TTA-UC, limitations of the current film, and the role of interfacial structure in dictating the performance.

Kenneth Hanson

Kenneth Hanson received a B.S. in Chemistry from Saint Cloud State University (2005), his Ph.D. from the University of Southern California (2010), followed by an appointment as a postdoctoral scholar at the University of North Carolina at Chapel Hill (2010–2013). His independent research career began in 2013 at Florida State University as a member of the Department of Chemistry & Biochemistry and is affiliated with the Materials Science & Engineering program. His current research interests include the design, synthesis, and characterization of photoactive molecules/materials with particular emphasis on manipulating energy and electron-transfer dynamics at organic–inorganic interfaces using multilayer self- assembly.

Professor Tehshik Yoon

Department of Chemistry

University of Wisconsin-Madison

Abstract

Stereocontrol in Photochemical Reactions

Photochemistry is intriguing as a synthetic tool because the absorption of light by an organic molecule results in the formation of exceptionally energetic reactive intermediates that can react in ways that are inaccessible to ground-state molecules. However, this high reactivity is also a challenge for stereoselective synthesis: control over the stereochemistry of photochemical reactions, particularly using enantioselective catalysts, has been a long-standing challenging synthetic problem with few general solutions. We recently developed a strategy that utilizes privileged chiral Brønsted acid scaffolds to control both the absolute and relative stereo- chemistry of complex [2+2] photocycloadditions. These reactions have enabled a general, concise, and stereocontrolled strategy for the synthesis of the truxinate and truxillate natural products.

Tehshik Yoon

Tehshik Yoon is a Professor of Chemistry at the University of Wisconsin–Madison. He earned his Ph.D. with Prof. David MacMillan, first at Berkeley and then at Caltech. After finishing graduate school in 2002, he became an NIH postdoctoral fellow in the laboratory of Prof. Eric Jacobsen at Harvard. Tehshik has been on the faculty at UW–Madison since 2005. His research group has broad interests in organic synthesis and catalysis. In particular, the Yoon group has been pioneering the use of transition metal photo catalysts in synthetically useful transformations promoted by visible light. Tehshik’s efforts in teaching and research have earned him a variety of prestigious of awards, including an NSF CAREER Award (2007), the Research Corporation Cottrell Scholar Award (2008), the Beckman Young Investigator Award (2008), the Amgen Young Investigator Award (2009), an Alfred P. Sloan Research Fellowship (2009), an Eli Lilly Grantee Award (2011), a Friedrich Wilhelm Bessel Award from the Humboldt Foundation (2015), and an ACS Cope Scholar Award (2019)

Professor Grace A. Lasker

Teaching Professor and Director of Health Studies

University of Washington Bothell

Abstract

“Implementing systems-thinking and sustainability frameworks for justice-centered change”

Recent global events, and those particularly in the United States, have revealed systemic discrimination related to race, culture, and other identities that have created environments that are neither inclusive nor equitable. Everyone, but particularly STEM-adjacent individuals, must recognize their role in removing barriers and biases that perpetuate racism and discrimination, thus preventing a true path toward equitable sustainability globally. By employing an anti-racism and anti-discrimination lens within a systems-thinking framework, we can solve global issues related to sustainability and social justice.

Grace A. Lasker

Dr. Grace Lasker is a Teaching Professor and Director of Health Studies at the University of Washington Bothell. Her research focuses on the intersection of toxicology, green chemistry, and public health. Her current passion is in supporting others through applying principles of social and environmental justice pedagogy and praxis in training the next generation of practitioners as they transition their advocacy and practice into creating equitable spaces and opportunities. She is a certified nutritionist (CN) and a Master Certified Health Education Specialist (MCHES).

Professor Alan Heyduk

Department of Chemistry

University of California, Irvine

Abstract

H-atom and Hydride Transfer Reactivity of Coordination Complexes with Redox-Active Ligands

Redox-active organic molecules of the ortho-quinone family have long been known to engender interesting electronic properties when bound to metal ions. The term electronic “non- innocence” was coined to describe those coordination complexes in which the frontier orbitals of the coordinated ligand were spatially and energetically proximate to the frontier orbitals of the metal ion, resulting in elaborate redox manifolds that could not be described adequately using traditional metal oxidation state and d-orbital electron-count models. The rich redox chemistry of these metal complexes presaged diverse reactivity patterns, and coordination complexes with redox-active ligands have been deployed in a variety of stoichiometric and catalytic reactions where the ability to mediate multi-electron bond-making and bond- breaking steps is critical. More recently, we recognized that many redox-active ligands can store one or more protons in addition to their ability to store redox equivalents. This talk will include recent results from our lab to benchmark the thermodynamic and kinetic parameters of proton-coupled electron-transfer (PCET) reactions of coordination complexes with redox-active ligands. The goal of this endeavor is to develop molecules that can effect net H-atom or hydride transfer and to apply this reactivity to the oxidation or reduction of fundamentally-interesting and practically-important small-molecule substrates.

Alan Heyduk

Alan Heyduk was born and raised in the northeast suburbs of Cleveland, Ohio. A first-generation college graduate, he received his B.S. in Chemistry from The Ohio State University where he did undergraduate research on the photochemistry of [CpFe(CO)2]2 with Professor Bruce Bursten. Upon graduation he joined a now defunct start-up company, Commodore Environmental Services, that developed remediation chemistry for halogenated organic waste streams. After a year in “the real world,” he returned to school, and in 2001 he earned his PhD from MIT under the guidance of Professor Dan Nocera, for his study of the photochemical cleavage of hydrohalic acids by two- electron mixed-valence complexes of rhodium. An NIH postdoctoral fellowship studying C–H bond activation with Professor John Bercaw at Caltech led to a faculty position at UC Irvine, where he started in 2003 and where he is currently a Professor in the Department of Chemistry.

Karen L. Wooley

University Distinguished Professor

Departments of Chemistry, Chemical Engineering, and Materials Science
& Engineering

Texas A&M University

Abstract

Structural, Topological and Morphological Diversities for Sustainable, Digestible Polymers Derived from Carbohydrates as Natural Product-based Polymers that Address Health-Food-Energy-Water Challenges: A story of pivots to overcome adversities while pursuing ambitions

A primary interest in the Wooley laboratory is the production of functional polymers from renewable sources that are capable of reverting to those natural products once their purpose has been served. A long- standing focus has been the development of synthetic methodologies that transform sugars, amino acids and other natural products into polymer materials. This approach allows for the production of functional polymers from renewable sources that are capable of reverting to those natural products once their purpose has been served. This holistic life cycle approach is of importance from the perspectives of sustainable sourcing of materials feedstocks, while creating mechanisms for breakdown of the polymer materials after useful lifetime is complete, and providing for biological and environmental resorption of breakdown products. The overall process impacts the need to address the increasing accumulation and associated hazards of plastic pollution from the environmental persistence of non-degradable, petrochemically-sourced polymer systems. Moreover, inherent diversities of natural products provide opportunities to expand the scopes, complexities and properties of polymers, by utilizing fundamental organic chemistry approaches. This presentation will highlight the development of synthetic methodologies for the preparation of sustainable polymers, block polymers and crosslinked network materials from carbohydrates, taking advantage of their stereochemical complexities and invoking in-situ structural metamorphoses to produce degradable polymers of diverse compositions, regio- and stereochemistries, and that can be made to exhibit a range of properties. Target materials are designed for potential applications in diverse areas, from energy, to medicine, to the environment. Examples will highlight contributions that polymer chemistry can make toward bulk technological materials that are capable of impacting global needs, such as water-food-energy-health, and the grand challenges that must be solved in the coming decade, while also emphasizing the need for flexibility to achieve ambitions while overcoming unintentional consequences.

Karen L. Wooley

Karen Wooley holds the W. T. Doherty-Welch Chair in Chemistry and is a University Distinguished Professor at Texas A&M University. She studied at Oregon State University (B.S., 1988) and Cornell University (Ph.D., 1993). The first sixteen years of her independent academic career were spent at Washington University in St. Louis, Missouri and she then relocated to Texas A&M University in July 2009. In addition to her academic positions, she is the co- founder and President of Sugar Plastics, LLC, and Chief Technology Officer of Teysha Technologies, LTD. Research interests include the synthesis and characterization of degradable polymers derived from natural products, unique macromolecular architectures, complex polymer assemblies, and well-defined nanostructured materials. She has designed synthetic strategies to harness the rich compositional, regiochemical and stereochemical complexity of natural products for the construction of hydrolytically-degradable polymers, which have impact toward sustainability, reduction of reliance on petrochemicals, and production of biologically-beneficial and environmentally-benign natural products upon degradation – these materials are expected to impact the global issue of plastic pollution and address challenges resulting from climate change. Recent awards include election as a Fellow of the American Academy of Arts and Sciences (2015), National Academy of Inventors (2019), American Association for the Advancement of Science (2020), American Institute for Medical and Biological Engineering (2020), and National Academy of Sciences (2020); she was also named as the 2021 Southeastern Conference (SEC) Professor of the Year.

Professor Peter A. Crozier

School for the Engineering of Matter, Transport and Energy

Arizona State University

Abstract

Atomic-Level Probing of Structural Dynamics in Catalytic Nanoparticles: Fluxionality and Functionality

Many promising energy conversion and storage options rely on thermal, thermochemical, photochemical and electrochemical processes which often depend on materials functionalities such as transport and reactivity. For example, in a heterogeneous catalyst, nanoparticle surfaces and interfaces orchestrate the kinetic pathways for chemical conversion processes which are controlled by charge/mass transport and reactivity at so-called active surface sites. Functionalities such as transport and reactivity involve motion of atomic species in or on the materials which can also lead to time-varying perturbations, distortions and destabilizations of the crystal lattice. There is an increasing recognition that in order to develop a deep understanding of transport and reactivity, it is critical to characterize the associated structural dynamics, so- called fluxionality. Fluxional atomic motion and migration is now observable with advanced in situ and operando transmission electron microscopes, and spatio-temporal analysis is providing new insights into local transport and reactivity pathways. For example, reducible oxide catalysts play a critical role in many redox reactions whereby oxygen exchange with the lattice is a central functionality (e.g. Mars van Krevelen process). Using CeO 2 as a model system, spatio-temporal analysis of cation fluxionality reveals variations in the oxygen vacancy creation and annihilation rates at different sites on nanoparticle surfaces. Supported metal catalyst (Pt, Ru) reveal a rich diversity in fluxional behaviors associated with processes such as CO oxidation.

Spatio-temporal characterization of atomic level fluxional behavior is a relatively unexplored area and is associated with large, noisy datasets which require novel approaches to data processing such as machine learning. Nanoparticles showing high degrees of fluxionality behave in a stochastic manner where the system transitions from a stationary metastable state to a series of rapidly changing unstable configurations. The behaviors are complex but are driven by strain and surface diffusion resulting in vacancy creation/ annihilation, formation of stacking faults, and temporary loss of long-range order. The structures of the metastable states, and the chemical triggers the lead to intense instability, are not well described or understood and must be characterized. Some structural dynamics appears to correlate with surface chemical interactions and catalytic functionality but, like the case for enzymes, the complexity of the behavior complicates the interpretation.

Peter A. Crozier

Peter A. Crozier is a Professor of Materials in the School for Engineering of Matter, Transport and Energy at Arizona State University. He has extensive experience in developing and applying advanced transmission electron microscopy techniques to problems related to energy and the environment with special emphasis on electroceramics, catalytic materials and atmospheric aerosols. He has 20 years of experience in developing and applying the technique of advanced transmission electron microscopy to problems in catalytic materials and oxide electrolytes. He is also applying electron energy-loss spectroscopy to determine the optical and vibrational properties of materials. He is a Fellow of the Microscopy Society of America and also a member of the Materials Research Society, the North American Catalysis Society and the American Ceramics Society. He serves on the editorial board of Microscopy Today and was the President of the Microscopy Society of America. He has organized numerous workshops, schools and symposia and has published more than 200 archival journal and book articles.

Tomohiro (Tomo) Kubo

Assistant Professor

Department of Chemical Science & Engineering

Tokyo Institute of Technology

Abstract

Controlled Polymerization of Renewable Monomers for Functional and Degradable Polymers

In light of increasing environmental concerns, the development of sustainable polymers for a circular economy has become a critical need. One promising approach for producing environmentally-friendly polymers is through the use of biorenewable feedstocks. This presentation encompasses our recent efforts in developing synthetic methods that transform abundant biobased compounds into novel polymeric materials. As an example of our approach, we have demonstrated the synthesis of well-defined functional polymers with adhesive properties through the controlled polymerization of renewable vinyl monomers. In more recent work, we have achieved the synthesis of degradable vinyl polymers by utilizing a renewable compound as a comonomer. Our results demonstrate the potential of these synthetic methods for producing sustainable polymers with desirable properties.

Tomohiro (Tomo) Kubo

Tomohiro (Tomo) Kubo is an Assistant Professor in the Department of Chemical Science and Engineering at the Tokyo Institute of Technology. He earned a BS in Chemistry and Chemical Engineering from the University of Minnesota in 2013, and a PhD in Chemistry from the University of Florida in 2018 under the direction of Professor Brent Sumerlin. During his doctoral work, he focused on developing post-polymerization modification methods for functional polymer synthesis. He then worked with Professor Anne McNeil at the University of Michigan, where he focused on synthesizing well-defined conjugated polymers by catalyst-transfer polymerization. In 2020, he started his current position at the Tokyo Institute of Technology. He has received several awards, including the JST PRESTO award in 2022.

Professor Neha Garg

School of Chemistry & Biochemistry

The Georgia Institute of Technology

Abstract

Mapping microbial responses to biological and chemical environments using omics

Chemical crosstalk is universal to all life. This crosstalk is mediated by a large diversity of molecules including small molecules, metal ions, polysaccharides, nucleic acids, and proteins. Inter– and intraspecies communication using small molecules, referred to as natural products, allows microbes to sense quorum, form biofilms, evade attack, and respond to stress. Chemical crosstalk is circumstantial i.e. niche-specific, and essential to thrive. The Garg laboratory seeks to develop and apply mass spectrometry- based methods to 1) discover the role of chemical and biological environment in the regulation of crosstalk underlying microbe-drug, microbe-microbe, and microbe-host interactions, and to 2) discover small molecule natural products that fine-tune these interactions. Chemical discoveries are supported by the genetic manipulation of organisms, phenotypic assays, and by manipulation of the biological and chemical growth environments. This seminar will highlight recent progress in three research directions: 1) chemical interactions between human pathogens and clinically administered antibiotics, 2) the role of quorum sensing, bacterial pigmentation, and infection-relevant environment in the regulation of the production of microbial natural products, and 3) the description of natural product diversity as a guide to develop probiotics aimed at improving resilience of marine corals to secondary bacterial infections.

Neha Garg

Neha Garg is an Assistant Professor at Georgia Tech broadly interested in understanding how small molecules shape microbial composition in complex environments. Garg obtained her Ph.D. in 2013 from the University of Illinois at Urbana-Champaign with Professors Wilfred A. van der Donk and Satish K. Nair. Neha's dissertation work in Illinois was recognized by the Anne A Johnson work award and the Catherine Connor Outstanding Dissertation in Biotechnology award. She then worked with Professor Pieter C. Dorrestein as a postdoctoral research associate at the University of California, San Diego where she developed metabolomics methods to visualize microbial communities. Garg was awarded NSF CAREER Award and Sandia’s Laboratory Directed Research and Development award to develop – omics methods for investigating the function and regulation of microbially- produced natural products. She has received several teaching awards at Georgia Tech including Center for Teaching and Learning Junior Faculty Teaching Excellence Award and Vasser Woolley Award for Excellence in Instruction. The Garg laboratory applies interdisciplinary approaches in microbiology, microscopy, mass spectrometry, and genomics to unveil the role of microbial, host, and chemical environments in production of small molecule natural products.

Professor Kenichiro Itami

Department of Chemistry

Nagoya University, Japan

Abstract

Toward molecular nanocarbon biology

Nanocarbons have revolutionized materials science, but due to the stereotype of “carbon = materials”, they have not been widely utilized in the biology and biotechnology fields. In this lecture, I will introduce our exciting new endeavor trying to develop game- changing molecules for nanocarbon-based chemical biology and explore a new field of molecular nanocarbon biology. The goal of this project is to create molecular nanocarbons (structurally well- defined nanocarbon molecules) that bring about bio-innovation by molecular design and characteristics of nanocarbons that are not found in conventional biofunctional molecules. Making full use of our world’s most advanced technology in the precision synthesis of molecular nanocarbons, we expect to create molecular nanocarbons that will have huge impact on drug (nucleic acid) delivery, therapeutics, diagnosis, imaging, and protein-protein interactions. We will also explore and establish the new field of insect nanocarbon biology where we use insects or bacteria as a tool for the synthesis of new nanocarbon molecules.

Kenichiro Itami

Kenichiro Itami studied chemistry at Kyoto University, Japan, and completed his PhD in 1998 with Prof. Yoshihiko Ito. After being Assistant Professor at Kyoto University, he moved to Nagoya University as an Associate Professor in 2005, where he was promoted to Full Professor in 2008. In 2012 he created the Institute of Transformative Bio-Molecules (ITbM) in Nagoya University, serving as the principal investigator (also the founding director until March 2022). During 2013-2020, he was the Research Director of JST-ERATO Itami Molecular Nanocarbon Project. Since 2019, he has also been the Research Fellow at the Institute of Chemistry, Academia Sinica, Taiwan. The work of Ken Itami has centered on catalyst-enabling synthetic chemistry with broad directions including molecular nanocarbon materials, C-H activation catalysts, medicinal chemistry, and chemical biology. The representative achievement is the creation of a range of structurally uniform nanocarbons of fundamental and practical importance by bottom-up chemical synthesis. He is recognized as Highly Cited Researchers (Clarivate Analytics) 5 years in a row since 2017, with an h-index of 83.

Professor Kenichiro Itami

Department of Chemistry

Nagoya University, Japan

Abstract

Catalyst-enabled molecular nanocarbon synthesis

Molecular nanocarbons including nanographenes and polycyclic aromatic hydrocarbons are among the most important classes of compounds, with potential applications in nearly all areas of science and technology. Typically, molecular nanocarbons are structurally simple assemblies of benzene-based hexagons and one can imaginarily build up a range of structures with ease and the theoretically possible number of molecular nanocarbon structures (planar and nonplanar) is extraordinary. However, most of these molecules remain synthetically out of reach due to a lack of synthetic methods, and their potentially huge structure-property diversity has not been fully exploited. This lecture will highlight our programmable, diversity-oriented and growth-from-template synthesis methods for nanographenes based on annulative π-extension (APEX) concept. These methods allow accessing a range of previously untapped planar and nonplanar molecular nanocarbons such as warped nanographenes and infinitene.

Kenichiro Itami

Kenichiro Itami studied chemistry at Kyoto University, Japan, and completed his PhD in 1998 with Prof. Yoshihiko Ito. After being Assistant Professor at Kyoto University, he moved to Nagoya University as an Associate Professor in 2005, where he was promoted to Full Professor in 2008. In 2012 he created the Institute of Transformative Bio-Molecules (ITbM) in Nagoya University, serving as the principal investigator (also the founding director until March 2022). During 2013-2020, he was the Research Director of JST-ERATO Itami Molecular Nanocarbon Project. Since 2019, he has also been the Research Fellow at the Institute of Chemistry, Academia Sinica, Taiwan. The work of Ken Itami has centered on catalyst-enabling synthetic chemistry with broad directions including molecular nanocarbon materials, C-H activation catalysts, medicinal chemistry, and chemical biology. The representative achievement is the creation of a range of structurally uniform nanocarbons of fundamental and practical importance by bottom-up chemical synthesis. He is recognized as Highly Cited Researchers (Clarivate Analytics) 5 years in a row since 2017, with an h-index of 83.