【演講公告】
Thermal Transport in Nanostructured Materials
Dr. Dongyan Xu
Department of Mechanical and Automation Engineering
The Chinese University of Hong Kong
EE324 from 3-5 pm on 8/14.
Abstract
Nanostructured materials have attracted tremendous research interest due to their
unique thermal, electrical, and mechanical properties and their potential applications in
various energy devices. In this talk, I will discuss some of our recent work on thermal
transport in nanostructured materials. First, I will introduce our recent study on
phonon mean free path in the c-axis of graphite. Until very recently, it has been
commonly believed that phonon mean free path in the c-axis of graphite is very short,
only a few nanometers at room temperature. However, our experiments show that the
c-axis phonon mean free path of graphite could be as long as 200 nm at 300 K, much
longer than the commonly believed value. In the second part, I will talk about
thermoelectric transport studies of individual bismuth selenide nanoribbons. Bismuth
selenide is a traditional thermoelectric material. It has also been shown to be a threedimensional topological insulator possessing a bulk band gap and gapless electronic
surface states that are protected by time-reversal symmetry. We are interested in
studying how surface states affect thermoelectric transport in single bismuth selenide
nanoribbons. I will discuss some of our recent results on this topic.
Biography
Dr. Dongyan Xu received her B.Eng., M.Eng., and D.Eng. degrees from the
Department of Engineering Mechanics at Tsinghua University in 1998, 2004, and
2004, respectively. She received her Ph.D. degree from the Department of Mechanical
Engineering at Vanderbilt University in 2008. After that, she worked as a Postdoc
Fellow in the Department of Mechanical Engineering at the University of California,
Berkeley for two years. She joined the Department of Mechanical and Automation
Engineering, The Chinese University of Hong Kong, in 2010, where she currently is
an Assistant Professor. Her research interests include thermoelectrics, thermal
management, nanoscale heat transfer, and micro/nanofluidics.