讲座题目：Simulation of the Thin
Passivation Layers— for Aluminum Forming and Lithium-Ion
Yue Qi is an associate professor in the Chemical Engineering and Materials
Science Department at Michigan State University (MSU). She received her Ph.D.
in Materials Science from California Institute of Technology in 2001. She was a
co-recipient of 1999 Feynman Prize in Nanotechnology for Theoretical Work
during her Ph.D. study. After her Ph.D., she spent 12 years working at the
Chemical Sciences and Materials Systems Lab, General Motors R&D Center. At
GM, she developed multi-scale models starting from atomistic level to solve problems
related to forming and machining of lightweight alloys, and developing energy
materials for batteries and fuel cells. She won three GM Campbell awards for
fundamental research on various topics and TMS Young Leader Professional
Development Award. She transitioned from industry to academia in 2013 and
quickly built the “Materials Simulation for Clean Energy” Lab at MSU. Recently,
she received the 2017 TMS Brimacombe Medalist Award.
Spontaneously formed passivation layers, such as
oxides on the aluminum surface, can enable many important applications by
blocking the diffusion of the reacting species. Lithiated graphite, lithiated
silicon, and lithium metal, as current and future anode materials, are covered
by a passivation layer in battery cells due to spontaneous electrolyte
reduction reactions. This passivation layer must have“selective”transport properties: blocking electrons from
attacking the electrolytes, while allowing Li+ion to pass through
so the electrochemical reactions can continue, therefore it is often called
“solid electrolyte interphase (SEI)”. Despite the importance, their
structure-property relationship is largely unknown due to their nanometer
Using reactive molecular dynamics and density
functional theory calculations, the transport and mechanical properties can be
predicted and the chemical and structural evolution of these passivation layers
can be tracked. Several important examples will be discussed in this talk.
For the oxides formed on solid and liquid aluminum,
it is more ductile and stretchable than the crystalline Al2O3.
When it is embedded inside casting aluminum, the breaking point is at the
Al/oxide interface, serving as fatigue cracking nucleation sites.
For the SEI in Li-ion batteries, the fracture and
delamination of the SEI on Si electrode are simulated, leading todesign criteria for mechanically
stable coated Si nanostructures andbattery operating
guidelines to mitigate capacity loss due to trapped Li and coating
邀请人：尹冬弟 博士 email@example.com 材料科学与工程学院，材料加工系