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ACS Award in the Chemistry of Materials Symposium in Honor of Prof. Yury Gogotsi: Materials for High Rate Energy Storage
08:00am - 10:00am USA / Canada - Eastern - August 22, 2021 | Room: B203
Kelsey Hatzell, Organizer, Princeton University; Kelsey Hatzell, Presider, Princeton University
Division: [ENFL] Division of Energy and Fuels
Session Type: Oral - Hybrid
Division/Committee: [ENFL] Division of Energy and Fuels
Sunday
Fast energy storage processes: From double layer adsorption to high-rate redox reactions
08:00am - 08:30am USA / Canada - Eastern - August 22, 2021 | Room: B203
Patrice SIMON, Presenter, université Toulouse III, Paul Sabatier
Division: [ENFL] Division of Energy and Fuels
Session Type: Oral - Hybrid
The past years have shown important performance improvement in EDLCs performance thanks to the design of porous carbons and electrolytes with tailored properties. However, although EDLCs are now used in several applications including for the ever-growing electric mobility market (trams and hybrid electric vehicles), the main challenge for ECs lies in the improvement of their energy density.

This presentation will give an overview of the joint work achieved together with Prof Yury Gogosti on the effect of the electrolyte confinement on the capacitive performance of 3-Dimensional and 2-D materials.
We will start by the mechanistic study of ion adsorption in porous carbon electrodes, where the use of advanced electrochemical techniques such as quartz crystal microbalance (EQCM) revealed specific ion-carbon surface interactions responsible for improved electrochemical performance.
The second part of the talk will be focus on high-rate MXenes materials pioneered by Yury and M. Barsoum, and show how the careful control of the electrode architecture and surface composition have led to drastic improvement of the electrochemical performance.
Besides offering new opportunities for designing high energy density supercapacitors, this set of results also shows the major impact of Yury Gogotsi’s contribution to the field of energy storage.

Sunday
Understanding the role of confinement on electrochemical capacitance: Implications for high power energy storage
08:30am - 09:00am USA / Canada - Eastern - August 22, 2021 | Room: B203
Prof. Veronica Augustyn, Presenter, North Carolina State University
Division: [ENFL] Division of Energy and Fuels
Session Type: Oral - Hybrid
Many layered materials of interest for electrochemical capacitor applications are flexible hosts whose interlayers can accommodate not just ions but also solvents. When these “hybrid” materials are placed into an electrochemical environment, the distinction between surface and bulk becomes blurred since the electrochemical interface can now be viewed to extend into the interlayer. In this presentation, I will discuss fundamental aspects of charge storage under confinement using the example of birnessite, a model layered material that contains structural water. By combining multi-modal electrochemical characterization with computer simulations, we find that cation intercalation from aqueous electrolytes into birnessite appears to be mediated by the structural water. Its presence limits the interaction distance between the cation and the metal oxide, provides a degree of cation solvation within the interlayer, and stabilizes the overall layered structure during cation de-intercalation. These results demonstrate the importance of tuning the electrochemical “inner surface” for high power energy storage applications.
Sunday
3D printed energy storage devices
09:00am - 09:30am USA / Canada - Eastern - August 22, 2021 | Room: B203
Majid Beidaghi, Presenter
Division: [ENFL] Division of Energy and Fuels
Session Type: Oral - Hybrid
Advances in the development of self-powered devices and miniaturized electronics have increased the demand for on-chip energy storage devices that can deliver high power and energy densities in limited footprint areas. In the past two decades, various electrode materials and fabrication methods have been explored to fabricate micro-batteries and micro-supercapacitors with high energy and power densities. Recently, advances in the development of scalable additive manufacturing methods have encouraged more research in this field. Fabrication of three-dimensional (3D) energy storage devices has been demonstrated through additive printing processes compatible with a variety of electrode materials and substrates. In this talk, a summary of previous efforts and the current status of the research on the fabrication of on-chip energy storage devices will be presented. Then, the results of our recent studies on the 3D printing of micro-batteries and micro-supercapacitors will be presented. The effects of ink composition and properties as well as the printing process used in the fabrication of the electrodes on the microstructure of 3D electrodes and their electrochemical performance will be discussed.
Sunday
Concentrated mixed cation ’water-in-salt‘ solutions: Electrochemistry, solvation and local order
09:30am - 10:00am USA / Canada - Eastern - August 22, 2021 | Room: B203
Maria Lukatskaya, Presenter
Division: [ENFL] Division of Energy and Fuels
Session Type: Oral - Hybrid
Electrolytes are an essential component of energy storage devices. Electrolyte composition has a significant impact on the safety, price and performance of the battery. Intrinsically nonflammable aqueous electrolytes can offer safer battery operation and decreased associated toxicity but suffer from a smaller electrochemical stability window (and hence energy density) compared to traditional organic electrolytes. To circumvent the small electrochemical stability window, highly concentrated “water-in-salt”, WIS, lithium organic imide systems which demonstrate significantly wider stability windows were recently proposed.1,2 However, the toxicity often associated with organic imides and high price make the practical implementation of current water-in-salt electrolyte chemistries into commercial energy storage devices challenging.
We address the challenge of developing new formulations of water-in-salt electrolytes caused by the lack of lithium salts having water solubility high enough to satisfy the water-in-salt condition. The proposed mixed cation strategy can enable use of cheaper (by at least an order of magnitude) and more soluble salts featuring alkali cations beyond lithium, e.g. potassium acetate, to create the water-in-salt condition.3 We study co-dissolution of corresponding lithium and zinc salts, we show that such highly concentrated electrolytes can provide the same benefits of the extended voltage window as imide-based electrolytes and, demonstrate compatibility with traditional Li-ion or Zn-ion battery electrode materials while being low-cost and environmentally benign. In addition, we demonstrate the strong effect of the solution concentration on the solvation structure of the cations and local order in the potassium acetate-based WIS systems and correlate it with the electrochemical response of different Zn-ion and Li-ion based electrode systems.

Carbon Capture & Utilization: Conversion of CO2 to Chemicals & Fuels:
08:00am - 10:00am USA / Canada - Eastern - August 22, 2021 | Room: B218
Juliana Carneiro, Organizer, Georgia Institute of Technology; Kandis Gilliard-AbdulAziz, Organizer, University of California Riverside; Ambarish Kulkarni, Organizer, University of California Davis; Kandis Gilliard-AbdulAziz, Presider, University of California Riverside; Juliana Carneiro, Presider, ‍ ; Ambarish Kulkarni, Presider, University of California Davis
Division: [CATL] Division of Catalysis Science & Technology
Session Type: Oral - In-person
Division/Committee: [CATL] Division of Catalysis Science & Technology

Carbon Capture and Utilization (CCU) is seen as a means to mitigate the emissions of CO2 with the concomitant use of a catalytic component for the conversion of CO2 to fuels, chemicals and polymers. While research for CO2 capture and utilization can be broad, this symposium will focus on the thermocatalytic and electrocatalytic strategies for CO2 capture and utilization. This symposium will foster the discussion from different perspectives and provide insights to address existing challenges in advancing these technologies further.

Sunday
CO2 hydrogenation to hydrocarbons over heterogeneous catalysts
08:00am - 08:40am USA / Canada - Eastern - August 22, 2021 | Room: B218
Division: [CATL] Division of Catalysis Science & Technology
Session Type: Oral - In-person
Society is faced with a CO2 dilemma – we need to slow our production of the gas while simultaneously developing efficient methods to capture, store and/or use it. My group has focused on CO2 capture for over a decade, designing porous materials and processes for CO2 separation from different gas mixtures, including flue gases and ambient air. More recently, we have focused our attention on the conversion of CO2 to useful products, such as hydrocarbons.
In this presentation, I will briefly describe some of the key approaches to CO2 capture, followed by a more detailed description of two approaches for CO2 conversion being explored in my group, (i) a chemical looping pathway based on high temperature CO2 capture coupled with in-situ hydrogenation of the captured CO2 to produce methane or methanol, and (ii) conversion of dilute CO2 into aromatics via a process intensification approach pairing methanol synthesis and zeolite catalysis. The performance of these (i) alkali-promoted supported metal and (ii) mixed metal oxide / zeolite hybrid catalysts will be described.

Sunday
Cesium-promoted ethanol production from CO2 hydrogenation on Cu/ZnO(000) surface: Full mechanistic study
08:40am - 09:00am USA / Canada - Eastern - August 22, 2021 | Room: B218
Dr Xuelong Wang, Presenter, Brookhaven National Laboratory; Pedro Ramírez; Dr Jose A Rodriguez, PhD, Chemistry Department; Ping Liu, Brookhaven National Laboratory
Division: [CATL] Division of Catalysis Science & Technology
Session Type: Oral - In-person
Efficient conversions of CO2 into value-added chemicals such as alcohols are of great industrial and scientific interest. The Cu/ZnO/Al2O3 catalyst has been extensively studied and commercialized in the industry to produce C1 alcohol, methanol from CO2 hydrogenation. In contrast, for Cu-based catalysts, successful attempts to achieve the production of higher alcohols, such as ethanol, which is safer and offers higher energy density, are very limited, due to the difficulty in C-C bond coupling and thus low selectivity. Most Cu-based catalysts are active for the reverse water gas shift (RWGS) reaction and hydrogenation of CO rather; while the C-O bond activation is difficult, which hinders C-C bond formation. Promoters such as Fe have been reported previously, which can facilitate C-O bond dissociation over Cu catalysts. In addition, alkali metal promoters, including K and Cs, have also shown the capability of C chain growth over Cu-based catalysts. Yet, the reaction mechanism remains elusive.
Here, combining surface science experiments and DFT calculations, we present a detailed mechanistic understanding of the roles that Cs plays in ethanol production at the Cu-Cs-ZnO interface under CO2 hydrogenation condition. Our study not only leads to the discovery of new pathways for ethanol production from CO2 hydrogenation but also opens new possibilities to allow the highly active and selective CO2 conversion to higher alcohols on widely used and low-cost Cu-based catalysts.

Sunday
Development of a zero gap membrane electrode assembly carbon monoxide electrolyzer
09:00am - 09:20am USA / Canada - Eastern - August 22, 2021 | Room: B218
Division: [CATL] Division of Catalysis Science & Technology
Session Type: Oral - In-person
Carbon monoxide electroreduction is a rapidly developing field for the production of valuable chemicals. When coupled with CO2 capture and electrochemical conversion, it can be used as a clean CO2 negative process for the production of a variety of products. Carbon monoxide reduction has the distinct advantage over direct electrochemical CO2 reduction to multi-carbon products (C2+) in that it does not suffer from carbonate formation, allowing for higher feed conversion and electrolyte stability. This work focuses on the design and production of a zero gap membrane electrode assembly carbon monoxide electrolyzer which operates at low cell potentials (< 2.5 V) and industrially relevant current densities (> 300 mA/cm2) for the production of acetate and ethylene. Zero gap electrolyzers place the cathode and anode in direct contact with a conductive polymer membrane. This provides distinct advantages over conventionally studied three-compartment flow cell designs, where the cathode is in contact with an aqueous liquid electrolyte. Specifically, the use of a solid polymer membranes increases cell stability while decreasing the electrolyzer internal resistance. We demonstrate the high selectivity of the device for producing acetate and ethylene, achieving high Faradaic efficiencies as well as high molar production rates relative to other C2+ products. The system was also found to have improved current densities and cell voltages when compared to conventional three-compartment carbon monoxide electroreduction systems. The opportunity for products to be shuttled through the membrane, however, leads to a more complicated system when compared to three-compartment systems, where the products are solely captured in the catholyte. An investigation was therefore performed to determine both the anode’s as well as the membrane’s effects on the system’s product output and performance.
Sunday
Withdrawn
09:20am - 09:40am USA / Canada - Eastern - August 22, 2021 | Room: B218
Division: [CATL] Division of Catalysis Science & Technology
Session Type: Oral - In-person

Sunday
Efficient inteplay of ZrO2 and Ni0 for photocatalytic CO2 conversion into mehtane monitored using 13CO2 and EXAFS
09:40am - 10:00am USA / Canada - Eastern - August 22, 2021 | Room: B218
Division: [CATL] Division of Catalysis Science & Technology
Session Type: Oral - In-person
The reaction mechanism of CO2 photoreduction into methane was elucidated by the time-course monitoring of the mass chromatogram, in situ Fourier transform infrared (FTIR) spectroscopy, and in situ extended X-ray absorption fine structure (EXAFS). Under13CO2, H2, and UV–visible light, 13CH4 was formed at a rate of 0.98 mmol h−1 gcat−1using Ni (10 wt%)–ZrO2 that was effective at 96 kPa. Under UV–visible light irradiation, the 13CO2 exchange reaction and FTIR identified physisorbed/chemisorbed bicarbonate and the reduction because of charge separation in/on ZrO2, followed by the transfer of formate and CO onto the Ni surface (Scheme 1). EXAFS confirmed exclusive presence of Ni0 sites. Then, FTIR spectroscopy detected methyl species on Ni0, which was reversibly heated to 394 K owing to the heat converted from light based on the analysis of Debye-Waller factor changes obtained by EXAFS. Heat reactions were much slower (Figure 1). Using D2O and H2, H/D ratio in the formed methane was in agreement with H/D ratio in reactant. This study paves the way for using first row transition metals for solar fuel generation and on-site fuel supply on planets using only UV–visible light.
<b>Scheme 1.</b> Proposed intermediate species during CO<sub>2</sub> exchange and photocatalytic CO<sub>2</sub> reduction.

Scheme 1. Proposed intermediate species during CO2 exchange and photocatalytic CO2 reduction.

<b>Figure 1. </b>Time course of <sup>13</sup>CH<sub>4</sub> and <sup>12</sup>CH<sub>4</sub> formation during the catalytic test exposed to (A) <sup>13</sup>CO<sub>2</sub> (2.3 kPa), H<sub>2</sub>O (2.3 kPa), and H<sub>2</sub> (21.7 kPa) under UV-visible light and (B) at 393 K, under dark (first 24 h) followed by under UV-visible light (6 h) both using Ni (10 wt%)-ZrO<sub>2</sub>-Reduced (0.020 g).

Figure 1. Time course of 13CH4 and 12CH4 formation during the catalytic test exposed to (A) 13CO2 (2.3 kPa), H2O (2.3 kPa), and H2 (21.7 kPa) under UV-visible light and (B) at 393 K, under dark (first 24 h) followed by under UV-visible light (6 h) both using Ni (10 wt%)-ZrO2-Reduced (0.020 g).


Circular Economy of Polymers:
08:00am - 10:00am USA / Canada - Eastern - August 22, 2021 | Room: A311-A312
Dr. Dimitris I Collias, Organizer, Proctor Gamble; Martin James, Organizer, Procter & Gamble Co; John Layman, Organizer; Dr. Dimitris I Collias, Presider, Proctor Gamble
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Division/Committee: [POLY] Division of Polymer Chemistry
Sunday
Advanced recycling: A pathway to circularity for critical multilayer flexible packaging
08:00am - 08:30am USA / Canada - Eastern - August 22, 2021 | Room: A311-A312
Dr. Timi Fadiran, Presenter, Sealed Air Corporation
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Multilayer flexible packaging optimizes materials while meeting the performance needs of critical products for food and medical applications. Individual layers in multilayer flexible packaging perform specific, necessary functions (e.g. oxygen barrier for shelf life extension) and enable the reduction of total amount of material used. The flexible packaging industry must continue to reduce waste and global carbon footprint. However, product waste impact is typically much greater than the packaging used to protect it. Shifting to monolayer solutions will lead to increased resource use and potential for product waste.
Advanced recycling solutions, such as pyrolysis and gasification, present a pathway to circularity for critical multilayer flexible packaging. First, these solutions offer high quality recycle content that can be used in critical applications such as food and medical packaging, allowing the flexible packaging industry to meet recycle content goals. Second, advanced recycling offers potential end of life solutions for hard-to-recycle multilayer flexible packaging. Design modifications of multilayer flexible packaging and dilution within the post-consumer waste stream should allow for these critical products to meet advanced recycling specifications.
In this work, the behavior and impact of multilayer products in a pyrolysis process are explored. The acceptability of flexible multilayers in pyrolysis and dilution of flexible multilayers in polyolefin rich streams are investigated. This work is critical to establishing advanced recycling specifications for post-consumer waste to drive a circular economy for flexible packaging.

Sunday
Smart pyrolysis for re-processing of PC/ABS polymer blends at end of useful life
08:30am - 09:00am USA / Canada - Eastern - August 22, 2021 | Room: A311-A312
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Given the global challenge of anthropogenic carbon in the earth’s atmosphere, there is increasing attention to intelligently managing carbon. Covestro is promoting the development of a circular economy of all materials, including plastics, even encompassing the most complex and elaborate value chains. Polycarbonate / acrylonitrile-butadiene-styrene polymer blends (PC/ABS) find application as an engineering thermoplastic used in electronics and industrial goods, automotive / transportation components, and building and construction / furnishings as a versatile material with an attractive value proposition for durable applications. While PC/ABS can be mechanically recycled in some instances, more comprehensive solutions are desirable. Chemical / solvolytic methods may be of broad utility but are not always attractive for polymer blends due to additional compositional complexity. Pyrolytic processes may have utility to accept worn down plastics at end of life with a modest latitude to readily accommodate variation of compositional inputs. Pyrolysis generally aims to convert such inputs to naphtha which may be reformed to chemicals. Smart pyrolysis aims to target the most suitable chemical “building blocks” to polymers, and tailor the process to attain those as directly as possible. This minimizes the overall number of processing steps. In this talk we shall discuss our motivation and laboratory project, as well as provide some initial results and conclusions specific to PC/ABS. The extrapolation to a production scale recycling operation looks interesting at the first pass.
Linear economy of plastics from the twentieth century is being transformed into a circular economy by further developing new technologies such as smart pyrolysis.

Linear economy of plastics from the twentieth century is being transformed into a circular economy by further developing new technologies such as smart pyrolysis.


Sunday
Withdrawn
09:00am - 09:30am USA / Canada - Eastern - August 22, 2021 | Room: A311-A312
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid

Sunday
Degradable vinyl polymers via photo controlled radical ring opening cascade polymerization
09:30am - 10:00am USA / Canada - Eastern - August 22, 2021 | Room: A311-A312
Jia Niu, Presenter
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Among the over 400 million tons of synthetic polymers produced worldwide annually, approximately half are vinyl polymers generated by radical polymerization. The widespread use of vinyl polymers has posed a significant challenge to the environment, as their hydrocarbon backbones are resistant to degradation. While degradable vinyl polymers via radical ring-opening polymerization have attracted increasing attention in both laboratory and industry, a major challenge in this field is the unfavorable reactivity ratios between the cyclic monomer carrying labile functional groups and the acyclic vinyl monomers, leading to inadequate material properties and partial degradation. In this presentation, we describe a photocatalytic approach to degradable vinyl polymers with tunable main-chain composition via radical ring-opening cascade polymerization (rROCP). Radical copolymerization of the macrocyclic monomers and a broad collection of acrylates or acrylamides mediated by visible light at mild temperatures afforded vinyl copolymers with tunable degradable units evenly distributed in the polymer backbone. This study provided a powerful approach to a new generation of degradable polymeric materials.

Structure to Function in Supramolecular Polymers & Materials:
08:00am - 09:40am USA / Canada - Eastern - August 22, 2021 | Room: A313-A314
Pol Besenius, Organizer, University of Mainz; Roxanne Kieltyka, Organizer, Universiteit Leiden; John Matson, Organizer, Virginia Tech; John Matson, Presider, Virginia Tech; Rachel Letteri, Presider, Texas A&M University
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Division/Committee: [POLY] Division of Polymer Chemistry
Sunday
Self assembled saccharide functionalized amphiphilic metallacycles as biofilms inhibitor
08:00am - 08:25am USA / Canada - Eastern - August 22, 2021 | Room: A313-A314
Guosong Chen, Presenter
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Bacterial biofilms are troublesome in the treatment of bacterial infectious diseases due to their inherent resistance to antibiotic therapy. Exploration of alternative antibiofilm reagents provides opportunities to achieve highly effective treatments. Herein, we propose a strategy to employ self-assembled saccharide-functionalized amphiphilic metallacycles ([2+2]-Gal, [3+3]-Gal, and [6+6]-Gal) with multiple positive charges as a different type of antibacterial reagent, marrying saccharide functionalization that interact with bacteria via “sweet talking”. These self-assembled glyco-metallacycles gave various nanostructures (nanoparticles, vesicles or micron-sized vesicles) with different biofilms inhibition effect on Staphylococcus aureus (S. aureus). Especially, the peculiar self-assembly mechanism, superior antibacterial effect and biofilms inhibition distinguished the [6+6]-Gal from other metallacycles. Meanwhile, in vivo S. aureus pneumonia animal model experiments suggested that [6+6]-Gal could relieve mice pneumonia aroused by S. aureus effectively. In addition, the control study of metallacycle [3+3]-EG5 confirmed the significant role of galactoside both in the self-assembly process and the antibacterial efficacy. In view of the superior effect against bacteria, the saccharide-functionalized metallacycle could be a promising candidate as biofilms inhibitor or treatment agent for pneumonia.
Sunday
Withdrawn
08:25am - 08:50am USA / Canada - Eastern - August 22, 2021 | Room: A313-A314
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid

Sunday
Conditionally active electron transfer catalysts enabled by bioinspired remodeling of polymer secondary structure
08:50am - 09:10am USA / Canada - Eastern - August 22, 2021 | Room: A313-A314
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Here we will discuss recent results from our work in which we show conditionally active electron transfer catalysts can be constructed from DNA. The catalysts are comprised of two strands, one of which can be selectively switched between a G-quadruplex and duplex or single-stranded conformations. This switching ability arises from our recent discovery that perchlorate, a chaotropic Hofmeister ion, selectively destabilizes duplex over G-quadruplex DNA. By varying perchlorate concentration, we show that the device can be operated as a switch or signal amplifier. State switching can be achieved in three ways: thermally, by dilution, or by concentration. In each case, when operated in the presence of the cofactor hemin, the device catalyzes electron transfer in only the G-quadruplex state. Examples of secondary-structure remodeling are observed in life as well. Nucleic acids exhibit considerable polymorphism in biological systems, particularly in sequences that can form G-Quadruplexes. Several proteins can remodel G-quadruplexes, and both energy-dependent (i.e., helicases) and energy-independent systems that can do so have been reported. ATPdependent helicases are known to unwind G-quadruplex structures, and the RNA-binding protein Lin28 has been shown to unfold G-quadruplexes without the requirement for ATP. The structure switching performed by Hofmeister ions in this work thus amounts to a bioinspired means of performing such remodeling, which in turn enables a functional behavior (electron transfer).

Sunday
Supramolecular self-assemblies of cyanine dyes for tunable excitonic properties across the visible and shortwave infrared regions
09:10am - 09:25am USA / Canada - Eastern - August 22, 2021 | Room: A313-A314
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Cyanine dyes self-assemble into distinct architectures (sheets, nanotubes or bundles) facilitated by an interplay of solubility, sterics and π-π stacking. We modulate the supramolecular packing and topologies of these self-assemblies in order to tune and explore new photophysical behaviors that are conventionally inaccessible. Photophysical properties of these assemblies are determined by the nature of long range transition dipole coupling that is highly sensitive to geometric arrangement and topology. In linear chains, cofacial arrangement leads to blue shifts in optical transitions whereas head-to-tail arrangements lead to red shifts, called as H- and J-aggregates respectively. Here, we describe an unusual situation that arises from 2-dimensional (2D) transition dipole coupling in sheet-like aggregates that extend upto micron scale. In addition to traditional H- and J-aggregation, we find a new case of I-aggregation which shows intermediate characteristics of both aggregates. We provide mechanistic insights into the self-assembly of extended sheet-like structures using a thermodynamic equilibrium model and lay down general principles for selectively stabilizing an H- or J-aggregated structure, providing a supramolecular avenue for tuning photophysical properties across a broad spectral range. We demonstrate this by stabilizing six different dyes into extended 2D structures with absorptions spanning the visible and shortwave infrared (SWIR) wavelengths. Further, we relate the packing geometries within the extended 2D aggregates to their excitonic band structures ultimately providing supramolecular control over photophysical properties such as absorption/emission wavelengths and quantum yields. Overall, this work establishes molecular aggregation as a new avenue for tuning photophysical properties and thus, opens up supramolecular chromophoric systems to new functionalities including SWIR imaging, plexitonics, and telecommunications.

Sunday
Hydrogen bonding indigo photoswitches as building blocks to engineer photo adaptative materials
09:25am - 09:40am USA / Canada - Eastern - August 22, 2021 | Room: A313-A314
Division: [POLY] Division of Polymer Chemistry
Session Type: Oral - Hybrid
Generating molecular tools displaying supramolecular interactions enable to build materials with
properties that can evolve in response to different stimuli. Association/dissociation of these
supramolecular systems can indeed be triggered by changing conditions (e.g. temperature, addition of
polar solvent, pH…). Among them, light is of great interest owing to its selective and non-invasive nature.
In this work, we aim to design photo-adaptive materials relying on hydrogen bonding patterns
undergoing association/dissociation through a light-induced molecular movement. We choose to
develop such systems using N,N’- modified indigos as photo-switch and an Ureidopyrimidinone (Upy)
derivative as hydrogen bonding unit. In comparison to other photoswitches, indigo is attractive because
of the large spatial change involved during its isomerization, the red light used in the process and the
tunable thermal stability of the Z isomer (modulated by the nature of the N,N’-substituents).

In order to build relevant supramolecular systems from indigoid derivatives, we first explored several
synthetic pathways to modify indigo scaffolds with different N,N’-substituents and investigated the
photophysical properties of the resulting adducts. Efforts were specifically devoted towards the
preparation of functionalizable N,N’- or N-mono substitued indigo that could be engaged in amide
coupling reactions in order to insert the Upy moieties. The results presented will encompass studies on
the synthetic pathways that allow the obtention of such photoswitches as well as the chemical
modification’s influence on the photophysical properties and notably on the thermal half-life of the Zisomer
which could be tuned from a few seconds to several hours.

Division of Chemical Health & Safety Awards Symposium:
08:00am - 10:05am USA / Canada - Eastern - August 22, 2021 | Room: B207 - B208
Kimi Brown, Organizer, Presider; Debbie Decker, Presider, Retired; Joseph Pickel, Presider, Oak Ridge National Laboratory
Division: [CHAS] Division of Chemical Health & Safety
Session Type: Oral - Hybrid
Division/Committee: [CHAS] Division of Chemical Health & Safety
Sunday
Introductory Remarks
08:00am - 08:05am USA / Canada - Eastern - August 22, 2021 | Room: B207 - B208
Division: [CHAS] Division of Chemical Health & Safety
Session Type: Oral - Hybrid

Sunday
Lessons learned from incidents that shaped my passion for safety
08:05am - 08:35am USA / Canada - Eastern - August 22, 2021 | Room: B207 - B208
Robert Hill, Presenter
Division: [CHAS] Division of Chemical Health & Safety
Session Type: Oral - Hybrid
I celebrate the opportunities that I have had to work in the health and safety arena for many years. Clearly over time many aspects of safety have improved, but the constant change of our world provides new hazards and new challenges that will test our ability to keep all of us safe. During my lifetime I have learned lessons from my own mistakes and experiences, as well as incidents that had profound effects on others. In this talk I describe an incident where I was almost killed, an incident where I was overexposed to a chemical, and other experiences that fueled my passion for safety. I will present conclusions and suggest ideas that might lead to new approaches to improve the state of safety of others in the future.
Sunday
Enabling and empowering students: Strategies for maintaining a strong safety culture
08:35am - 09:05am USA / Canada - Eastern - August 22, 2021 | Room: B207 - B208
Ian Tonks, Presenter
Division: [CHAS] Division of Chemical Health & Safety
Session Type: Oral - Hybrid
The University of Minnesota Joint Safety Team has emerged as a standard-bearer for student-driven safety initiatives. In this talk, strategies for maintaining momentum within this type of program will be discussed from both a historical and personal perspective. Additionally, accident reporting metrics will be discussed in the context of new safety initiatives being carried out in the department.
Sunday
University of Iowa chemical safety and responsibility stewards: Finding our place in the chemistry department
09:05am - 09:35am USA / Canada - Eastern - August 22, 2021 | Room: B207 - B208
Jessica L DeYoung, Presenter, University of Iowa; Lindsey Applegate; Hannah Nenning; Madeline Parker; Leah J Scharlott, University of Iowa
Division: [CHAS] Division of Chemical Health & Safety
Session Type: Oral - Hybrid
University campuses around the country have created ‘joint safety teams’ (JSTs) of various stripes to supplement the research laboratory safety hierarchy. They fill a vital role by filling gaps in communication between front line researchers (graduate students) and higher-ranking decision makers (faculty). Some responsibilities of JSTs include disseminating information from faculty committees, liaising with campus environmental health and safety officers, developing or leading safety workshops, and generally promoting a culture of safe research practices. At the University of Iowa, our joint safety team is known as the chemical safety and responsibility stewards (CSARS). Our organization functions as most do but we are differentiated in graduate students being integrated into the core framework of the safety hierarchy. One example is when the COVID-19 pandemic began our organization stepped up to play a unique role by ensuring graduate students working as research and teaching assistants were provided with appropriate resources to work safely. The success of this effort shows the self-efficacy of student organizations. When given appropriate resources and a clear task, JSTs can make significant improvements in the working conditions of graduate researchers. Our contributions unrelated to the pandemic include recording first-year student safety training videos, creating demonstration outreach videos focused on safety, and organizing/hosting safety focused webinars. While we are still a young organization, we have found success in establishing our group as a contributing committee of the department within the greater JST network.
Sunday
Institutional structures and practices within academic chemical laboratories as predictors of safety behavior in individuals
09:35am - 10:05am USA / Canada - Eastern - August 22, 2021 | Room: B207 - B208
Division: [CHAS] Division of Chemical Health & Safety
Session Type: Oral - Hybrid
Over the last two decades, there have been numerous high-profile accidents in academic chemical laboratories across the world which have each led to institutional self-reflection and calls-to-action through tragedy, heavy fines, and public outcry. As a result, many academic institutions intensified their official safety policies and restructured their safety administration. However, the changes in top-down leadership seen in academia have unfortunately resulted in little long-term behavioral change in bench chemists and principal investigators. In part, this may be due to a nebulous and disparate leadership structure which leads to an over-emphasis on compliance rather than collaborative, proactive engagement. To address these emerging issues, we are implementing a web-based, self-administered standardized stratified survey to collect information from Ph.D. candidates in departments of chemistry, stratified by institutional research status, funding status, and geographical location. We use the Research Laboratory Safety Behavior Survey (RLSBS) as a predictor of safe behavior on the individual level along with our new standardized survey to gather information about leadership structures, relationships, training environments, resource availability, and institutional accessibility and to make conclusions about which structures and practices correlate the most with safe behavior.