Chemistry Colloquium Program

Time and location: Unless otherwise noted, seminars will be held on Fridays in the A101 Annex Auditorium at 3:30 p.m.. Check the individual notices posted  on bulletin boards or your e-mail box for confirmation of times and locations.  
 

Spring 2024 Schedule

Date Speaker Title Abstract Host
March 1, 2024 Dr. Daniel Abraham, Senior Scientist at Argonne National Laboratory Electrode Behavior during Fast Charging of Lithium Ion Cells

Rapid cycling of lithium ion batteries ( being developed for electric vehicles, is highly desirable Rapid charge is needed to meet customer demands of time parity with today’s gasoline powered cars rapid discharge is needed to deliver the high performance expected of electric vehicles The U S DOE has set a target charging time of 15 minutes 4 C rate) as a near term goal, further indicating that a 5 minute charge 12 C rate) could be a long term goal.

At higher cycling rates, however, the capacity, cycle life, and thermal stability of these LIBs is known to degrade The mechanisms responsible for this performance decline are being examined at Argonne National Laboratory as part of projects funded by the US DOE These mechanisms are believed to include the following heterogeneous Li intercalation/extraction reactions in the active particles, non uniform reactions across the porous electrode cross sections, fracture of anode and cathode particles, and lithium metal plating on the anode. A fundamental understanding of these processes is being gained by the application of various diagnostic techniques, including electrochemistry, diffraction, microscopy, spectroscopy and tomography.

During the presentation, results from the study of cells, containing layered oxide
cathodes and graphite anodes, subjected to rapid cycling will be highlighted In particular, the use of a microprobe reference electrode to monitor the onset of Li plating conditions will be examined and methodologies to investigate the lithium concentration gradients that develop in the electrodes during rapid cycling will be discussed.

Dr. Daniel Kuroda
March 22, 2024 Dr. Annette Taylor, Professor of the Department of Chemical and Biological Engineering at the University of Sheffield Control of enzyme-catalyzed processes and material formation in bioinspired systems My group combines experiments with kinetic modelling in order to understand and control aqueous phase catalysis and material formation in bioinspired chemical systems. Taking inspiration from nature or the use of natural components allows us to design functional materials and processes that are greener or more sustainable, but also harness the unique properties arising from feedback in natural systems. The research has a wide range of applications such as bio-reactors for fuel or food, materials formation or degradation, drug delivery and sensing. Here I will discuss some of our recent projects including: a) spatio-temporal control of gelation and use of watermelon seed enzymes; b) enzyme-catalyzed drug release in synthetic vesicles and c) control of material formation with microfluidic double emulsions. Dr. John Pojman