Event
Special Seminar: Dr. Xin Guo, Huazhong University of Science and Technology
Friday, October 9, 2015
2:30 p.m.
3106 Martin Building
Amanda McCrum
301 405 9378
amccrum@umd.edu
Dr. Xin Guo
NTTP Chair Professor of Solid State Ionics
School of Materials Science and Engineering
Huazhong University of Science and Technology
“Defect chemistry of lithium ion conducting oxides: Li3xLa2/3-xTiO3 and Li7La3Zr2O12"
Abstract:
Solid state lithium ion conductors are favorable due to the high safety performance and electrochemical stability; however, they also suffer from the relatively low lithium ion conductivity. In most cases, solid state lithium ion conductors are present in the form of polycrystals; therefore, grain bulk and grain boundaries are the two crucial parts of the microstructure. In this presentation, we evaluate the lithium ion conductivities of Li3xLa2/3-xTiO3 (LLTO) with perovskite structure and Li7La3Zr2O12 (LLZO) with garnet structure, with the ionic conductivities of the grain bulk and grain boundaries being addressed from the point of view of defect chemistry. We try to give answers to the following questions: How to improve the lithium ion conductivity? How to suppress the electronic conductivity? Does the oxygen ion conductivity play any role? What is the physical origin of the low grain boundary conductivity?
Speaker Biography:
Xin Guo is the National Thousand Talent Program (NTTP) Chair Professor at School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, China. 1998 to 2002, he worked at the Max Planck Institute for Solid State Research, Stuttgart, Germany, as a guest scientist, and 2002 to 2012, at the Research Center Juelich, Juelich, Germany, as a senior scientist. In between, 2004-2005, he also worked with Dr. Wachsman at the University of Florida for one year. In 2005, he received the Ross Coffin Purdy Award from the American Ceramic Society. His current research interests are: ceramic gas sensors, ionic devices for information storage, logic operations and neural function imitation, solid state lithium ion batteries and supercapacitors, point defects and extended defects in complex oxides, ionic Hall Effect, low dimensional (0 and 1 dimensional) oxides and nano-architectured devices, 3D printing of ceramics.
Xin Guo
Laboratory of Solid State Ionics, School of Materials Science and Engineering,
Huazhong University of Science and Technology, Wuhan 430074, P.R. China
E-mail: xguo@hust.edu.cn
