Unconventional Thermoelectrics: from new materials to energy conversion devices

The development of advanced thermoelectric materials for effective thermoelectric devices is an evolving challenge in energy conversion technologies. The required improvement over toxic and expensive state of the art bulk semiconductor thermoelectrics needs a deep understanding of the thermoelectric conversion processes.

Scope

The aim of the symposium is to assemble scientists from universities, scientific institutes as well as industry to promote co-operations on thermoelectric materials development. The use of solar, geothermal or waste heat as an energy source is an attractive and environmentally clean way to generate electrical power. With a thermoelectric (TE) device heat can be directly converted into electricity. TE devices work independently of mechanical and chemical conversion processes. Thus, they are emission free, noiseless, and extremely durable. A conventional TE converter has an efficiency of 5-10%. It consists of numerous thermocouples, comprising p- and n-type thermoelements connected electrically in series and thermally in parallel. Heating one side of a semi-conducting thermoelectric material allows electrons and holes to thermally diffuse along the temperature gradient and to carry their charge with them. The amount of electrical power so produced depends on the thermoelectric conversion efficiency of the device and the heat flux. The relevant material parameters, i.e., thermopower, electrical, and thermal conductivities, are interrelated by the specific electronic structure of the material. Conventional TE devices, e.g., for space applications, aim rather at high reliability than at high energy conversion efficiency and low cost. These devices are based on expensive and toxic materials like tellurides and have low temperature stability when exposed to an oxidizing atmosphere. For the future broad use, cheap and environmentally benign materials have to be found. Compounds exhibiting low thermal conductivity, small resistivity, and a large Seebeck coefficient are required. Since for most materials the thermal and electrical conductivities are interconnected by the Wiedemann-Franz-law, the development of a material breaking this relationship is the great scientific challenge to be addressed.  

Hot topics to be covered by the symposium 

• Efficient thermoelectric power conversion

• Novel thermoelectrics

• Thermoelectric oxides

• Half-heuseler compounds

• Nanothermoelectrics

• Nano-processed bulk materials

• Thin films

• Thermoelectric modules

• All oxide thermoelectric generators

• High temperature energy conversion

• Efficient conversion of solar and geothermal heat

• automotive applications

• Spin entropy and strong correlation

• Thermionic energy conversion

• Waste heat recovery

• Tuning of heat and electronic conductivity in solids

Symposium organizers

Anke Weidenkaff 
Empa
Ueberlandstrasse 129
CH-8600 Duebendorf-Zuerich
Switzerland
Phone: +41 44 823 4131 
Fax: +41 44 823 4034 
anke.weidenkaff@empa.ch

Antoine Maignan 
CNRS 
Laboratoire CRISMAT, ENSICAEN
France
Phone: +33 (0)2 31 45 26 34 
Fax: +33 (0)2 31 95 16 00
antoine.maignan@ensicaen.fr

Heiner Linke
Lund University
Solid State Physics
Box 118, 22100 Lund, Sweden 
Phone: +46 70 414 0245 
heiner.linke@ftf.lth.se  

Ichiro Terasaki
Nagoya University
Dept. of Physics
Nagoya 464-8602, Japan 
Phone & Fax. +81-52-789-5255 
terra@cc.nagoya-u.ac.jp