Title: Academic Lecture 68: Electrical and Phonon Transport Control of Inorganic Thermoelectric Materials and Research on Flexible Devices

School of Physics and Optoelectronic Engineering

Date: 2019/12/17, 9:49:00

Speaker: Professor Miaolei, Guilin University of Electronic Technology

Time: Thursday, December 19, 2019, 14:30-15:30

Location: Room 1006, Zhiyuan Building (Formerly Physics and Optoelectronic Building)

Abstract:

Thermoelectric materials and devices enable direct conversion between heat and electricity, offering advantages such as miniaturization, flexibility, noise-free and emission-free operation, as well as safety and reliability. They provide a convenient and environmentally friendly approach for cooling, heating, and recovering electricity from low-quality heat energy, which is essential for various human activities. However, improving the thermoelectric performance is challenging due to the interdependent coupling among the three main parameters reflecting thermoelectric properties in thermoelectric materials: Seebeck coefficient, electrical conductivity, and thermal conductivity. This limitation restricts the application range of thermoelectric devices. In recent years, the idea of separating and controlling electron and phonon transport has greatly advanced the improvement of thermoelectric materials' performance. Additionally, the flexible design of thermoelectric devices holds promise for facilitating their applications. This report focuses on the study of electrical and phonon transport control of materials such as MgAgSb, SnSe2, Cu2S, and Ag2Se, as well as the research on the flexibility of inorganic thermoelectric materials. For instance, the presentation discusses the doping of Zn and thermal treatment of MgAgSb to enhance crystallinity and conduction band convergence, thereby increasing the electrical transport performance (power factor), and the introduction of various micro-nanostructures (grain boundaries, phase boundaries, nanoscale pores, and dislocations) to scatter phonons and reduce thermal conductivity. Furthermore, the deposition of inorganic thermoelectric materials such as Ag2Se and Ag2Te on filter paper followed by cold pressing to prepare flexible inorganic material thermoelectric films. These findings offer new guidance for improving the thermoelectric performance of inorganic materials and the flexibility of their devices.

Speaker Bio:

Professor Miaolei is a female professor and Ph.D. supervisor at Guilin University of Electronic Technology and leads the Guangxi "Bagui Scholar" team. She also serves as a visiting researcher at the Materials Technology Institute of the Japan Fine Ceramics Research Center and as a council member of the Special Ceramics Division and Thermoelectric Division of the Chinese Ceramic Society. Her research interests include solar energy photothermal conversion, semiconductor thermoelectric conversion materials and devices, and building energy conservation. She has published 175 SCI papers with approximately 3000 citations and an H-index of 30. Her representative research has been published in international academic journals such as Advanced Functional Materials, Nano Energy, and Applied Energy in the fields of materials and energy. She has undertaken more than twenty projects funded by the Ministry of Science and Technology, the National Natural Science Foundation of China, and local scientific research projects. She has received numerous awards and honors including the 2003 Japan "Pioneer Innovation-Advanced Technology" Award, the 2011 China-Japan Ceramic Society Technology Exchange Award, the third prize of the Guangdong Provincial Science and Technology Progress Award in 2012, the 2013 Guangzhou Outstanding Female Technologist Award, the 13th Guangxi Youth Science and Technology Award in 2015, the second prize of the Guangxi Science and Technology Award in 2016, the second prize of the Autonomous Region-level Teaching Achievement Award for Higher Education in Guangxi in 2017, and the National March 8th Red Flag Bearer Award in 2018, among others.

All teachers and students are welcome to attend!