Department of Chemistry Seminar - Molecular LOGICS for Reactive Electrochemical Interphases
Supporting the below United Nations Sustainable Development Goals:支持以下聯合國可持續發展目標：支持以下联合国可持续发展目标：
Speaker: Dr. Weilai YU
Hosted By: Professor Jianzhen YU
Abstract
Electrochemical materials operate through dynamic interphases that emerge under nonequilibrium chemical and electric-field conditions. In lithium-metal batteries, the solid–electrolyte interphase (SEI) mediates coupled electron–ion transfer and interfacial reactivity. Despite decades of investigation, rational design of the SEI remains elusive because its formation arises from competing molecular decomposition pathways and nanoscale chemical heterogeneity.
In this talk, I will present our efforts to program interphase chemistry by uncovering the molecular LOGICS that govern interphase formation at reactive metal surfaces. By integrating electrochemical measurements with non-perturbative spectroscopy (non-washing X-ray photoelectron spectroscopy and synchrotron X-ray absorption spectroscopy), we directly resolve which electrolyte-derived species are selectively stabilized within the interphase and how their coordination environments evolve during electrochemical cycling. We show that semi-soluble anion-derived species (e.g., LiF) preferentially accumulate to form a nanoconfined inorganic–organic hybrid interphase with emergent transport and mechanical characteristics.
We further reinterpret the classical electric double-layer (EDL) effects within this chemically heterogeneous interphase, revealing how localized electric fields and ion-specific interactions regulate metal deposition reversibility. Together, these results establish molecular-level principles for controlling electrochemical interfaces and suggest a broader paradigm of programmable interphase chemistry in energy and catalytic materials.
About the Speaker
Weilai Yu is an incoming Assistant Professor in the Department of Chemical Engineering and Applied Chemistry at the University of Toronto and a recipient of the inaugural Faculty Accelerator Award from the Acceleration Consortium. He received his B.S. in Chemistry from Wuhan University and his Ph.D. in Chemistry from the California Institute of Technology (Caltech), followed by postdoctoral research in Chemical Engineering at Stanford University.
His research centers on molecular-scale chemistry at electrochemical interfaces. By integrating electrochemistry with advanced spectroscopy and materials chemistry, his work elucidates the mechanisms governing interphase formation, structure, and reactivity in energy and catalytic systems.