MSE Special Seminar: Beyond structural and chemical imaging in a TEM
Wednesday, March 11, 2020
12:00 p.m.
Kay Boardrooms, Kim Engineering Building (first floor), UMD
For More Information:
Sherri Tatum
statum12@umd.edu

Speaker:  Miaofang Chi, Ph.D., Center for Nanophase Materials Sciences, Oak Ridge National Laboratory

Title: Beyond structural and chemical imaging in a TEM: New opportunities for understanding interfaces in energy materials

Abstract:

Revealing atomic arrangements and identifying single-atom chemical species in materials can now be routinely achieved in many microscopy labs. Electron microscopy has undergone significant technical developments over the past several decades. These novel capabilities have made substantial contributions to energy materials research, especially in terms of exploiting functional interfaces and defects, which can often provoke unexpected properties. Interrogating such defects poses challenges for many characterization tools. Recent developments in scanning transmission electron microscopy (STEM), including atomic-scale in situ imaging, four-dimensional (4D)-STEM, and monochromated EELS have opened up unprecedented opportunities. In this presentation, I will introduce these capabilities and highlight examples demonstrating how these capabilities allow us to (1) track chemical reactions and elemental diffusion in catalysts in response to changing environments in real-time; (2) map local charge distribution and correlate with the chemistry and structure of local features at the atomic-scale – an example of probing the interfacial charge transfer at catalyst interfaces will be given; and (3) reveal electronic band structures and phonon modes of interfaces and link microscopic observations to the performance of solid electrolytes for batteries.

Bio:

Miaofang Chi is a senior staff scientist at the Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National Laboratory (ORNL). She received her Ph.D. in Materials Science and Engineering from University of California, Davis in 2008. Her primary research interest lies in the advancements and applications of novel electron microscopy techniques in energy and nanotechnology research, especially in the understanding of interfacial charge transfer behavior in energy storage and nanoelectronics systems. She was awarded the Burton Metal by the Microscopy Society of America (2016). She received the ORNL Director’s Award for Outstanding Individual Accomplishment in Science and Technology (2015) and the ORNL’s Early Career Research Award (2015). Miaofang is the author and co-author of more than 150 peer-reviewed journal articles. She was named to the Clarivate’s 2018 list of Highly Cited Researchers.

This Event is For: Clark School