"Thermoelectric Energy Conversion: Materials, Transport, and Devices"

Dr. Gang Chen, Professor of Power Engineering at Massachusetts Institute of Technology

February 8th (Friday), 2:00pm
Engineering Science Building (ESB), Rm 2001

Thermoelectric devices exploit thermal energy carried by electrical charges for the conversion between heat and electricity for cooling, heating, and power generation applications. Efficient thermoelectric energy conversion calls for materials with good electrical conductivity and large Seebeck coefficient, but low thermal conductivity. In this talk, I will start with an introduction to thermoelectric effects, and move on to discuss ways to understand and engineer phonon and electron transport in thermoelectric materials to improve the materials’ performance. First-principles simulation on phonon heat conduction in bulk crystals reveals details on phonon scattering and mean free path distributions, and explains why III-V semiconductors have higher thermal conductivity than IV-VI and V-VI compounds. I will present a recently developed thermal conductivity spectroscopy technique to measure phonon mean free distribution and discuss experimental evidence on coherent contribution of phonons to heat conduction in superlattices. On electron transport, we extend the modulation doping concept used for 2D electron gas to 3D nanostructures and design core-shell nanostructures to create anti-resonant scattering. I will conclude the talk with a demonstration of flat-panel solar thermoelectric generators, which achieved 4.6% efficiency, with no optical concentration.

About Dr. Gang Chen:

Dr. Gang Chen is currently the Carl Richard Soderberg Professor of Power Engineering at Massachusetts Institute of Technology. He obtained his Ph.D. degree from UC Berkeley in 1993 working under then Chancellor Chang-Lin Tien. He was a faculty member at Duke University (1993-1997), University of California at Los Angeles (1997-2001), before joining MIT in 2001. He is a recipient of the NSF Young Investigator Award, the ASME Heat Transfer Memorial Award, the R&D100 Award, and the MIT McDonald Award for Excellence in Mentoring and Advising. He is a member of the US National Academy of Engineering, a Guggenheim Fellow, an AAAS Fellow, an APS Fellow, and an ASME Fellow. He has published extensively in the area of nanoscale energy transport and conversion and nanoscale heat transfer. He is the director of Solid-State Solar-Thermal Energy Conversion Center funded by the US DOE’s Energy Frontier Research Centers program.

Hosted by: Professor John Bowers, Electrical and Computer Engineering