Speaker Bio

Abstract:

Charged solid–liquid interfaces are primary sites for a wide array of chemical reactions in various systems including ion adsorption/desorption in natural environments, heterogeneous catalysis, and energy storage. Probing the interfacial structure at the atomic scale can provide a direct insight into the reaction mechanisms. In this presentation, I show how ion charge and hydration influence the speciation and dynamics of metal pollutants adsorbed at mineral–water interfaces based on in-situ observations using synchrotron high-resolution X-ray reflectivity. I also highlight how these structures can be modified with varying solution compositions that are relevant in natural environments. These experimental observations are compared with computational simulations to provide a more detailed insight into molecular-scale behaviors in complex interfacial phenomena. Finally, I discuss new opportunities and challenges for studies of interfacial geochemistry using the high brilliance and coherence from the 4th generation source of synchrotron X-rays.

Speaker’s Bio:

Sang Soo Lee is a Geochemist in the Chemical Sciences and Engineering Division at Argonne National Laboratory. He received his B.S. in the Department of Geological Sciences at Seoul National University (SNU), South Korea, in 1996, M.S. in the Department of Earth System Sciences at SNU in 1998, and Ph.D. in the Department of Earth and Environmental Sciences at University of Illinois at Chicago in 2007. His research in Argonne focuses on understanding the molecular-scale structure and energetics of solid­­–water interfaces that are relevant to many natural phenomena, including heavy metal contamination and remediation, mineral and organic interactions, and chemical evolution of Earth materials via interaction with natural fluids, through the application of synchrotron-based X-ray scattering and imaging techniques. He has also been involved in various synergistic activities. He was the chair of the Chem/Bio/Environmental Panel for Advanced Photon Source in 2017–2019, associate Editors for the Journal of the Mineralogical Society of Korea and PLOS One. He was on the Council Committee for the Clay Minerals Society. He has been on the Executive Committee for the ACS-Geochemistry Division for which he currently serves as the Chair-elect.