Energy from waste heat: how thermoelectric materials are designed and used

Seminars
24.04.2017
14:30
David Wang Auditorium, 3rd floor Dalia Maydan Bldg.
Prof. Mercouri G. Kanatzidis

The winner of  “Hershel and Hilda Rich Visiting Professorship 2017” – Prof. Mercouri G. Kanatzidis will be our guest during April 23-28, 2017 (Formal invitation will be sent later).

He will give 3 lectures during his visit, as follows:

24.4.17: Energy from waste heat: how thermoelectric materials are designed and used

26.4.17: Halide Perovskites: new high performance semiconductors

27.4.17: Inorganic chalcogenide solids: from discovery to design and applications

 

Recent advancements in thermoelectric materials involving nanostructuring semiconductors have create large excitement and highlighted the technology’s potential for energy efficiency and heat management on a commercial scale.  Nanostructuring is the process of embedding suitable second phase, in nanocrystalline form, inside a thermoelectric material. This process dramatically lowers the thermal conductivity of the composite and greatly enhances the conversion efficiency.  Waste-heat recovery with thermoelectric power generators can improve energy efficiency and provide distributed electricity generation. Energy-intensive industries, such as cement making, glass making, coal-fired power plants and metals production, generate enormous amounts of heat, and most of this heat is lost into the environment through smoke stacks and other means. Thermoelectric devices are very attractive because they convert thermal energy into electricity without requiring moving components. Current research in high performance thermoelectric materials involves nanostructuring, mesostructuring, band alignment, band engineering and other concepts. These are synergistic strategies for boosting the thermoelectric performance. To date, the dramatic enhancements in figure of merit achieved in bulk thermoelectric materials come either from the reduction in lattice thermal conductivity or improvement in power factors, or both. We will review the relationships between a) very large reduction of lattice thermal conductivity and all-scale hierarchical architecturing, b) enhanced Seebeck coefficients and intra-matrix electronic structure engineering and control of the carrier mobility with matrix/inclusion band alignment. The talk will give particular emphasis on the systems PbTe, PbSe, PbS and SnSe in which spectacular advances have been demonstrated.