Contradictory Transport Requirements for High ZT and Their Resolution
David J. Singh
Department of Physics and Astronomy, University of Missouri, Columbia MO 65211 USA
Email: singhdj@missouri.edu
Thermoelectric devices are used for direct conversion between thermal and electrical energy. Thermoelectric performance is characterized by a material dependent figure of merit ZT=σS2T/κ, where S is the Seebeck coefficient and the other symbols have their usual meanings. ZT measures the efficiency that can be obtained using given materials. While there is no thermodynamic limit on ZT, the inter-relationships of the transport quantities that enter this figure of merit make high high ZT a strongly contra-indicated property. This talk overviews these inter-relationships and ways of overcoming them, including quantitative measures of band structure features of importance to ZT, and thermal aspects.
This work was supported in part by the U.S. Department of Energy, Basic Energy Sciences, through the S3TEC Energy Frontier Research Center.