How much improvement in thermoelectric performance can come from reducing thermal conductivity?
Large improvements in the performance of thermoelectric materials have come from designing materials with reduced thermal conductivity. Yet as the thermal conductivity of some materials now approaches their amorphous limit, it is unclear if microstructure engineering can further improve thermoelectric performance in these cases. In this contribution, we use large data sets to examine 300 compositions in 11 families of thermoelectric materials and present a type of plot that quickly reveals the maximum possible zT that can be achieved by reducing the thermal conductivity. This plot allows researchers to quickly distinguish materials where the thermal conductivity has been optimized from those where improvement can be made. Moreover, through these large data sets we examine structure-property relationships to identify methods that decrease thermal conductivity and improve thermoelectric performance. We validate, with the data, that increasing (i) the volume of a unit cell and/or (ii) the number of atoms in the unit cell decreases the thermal conductivity of many classes of materials, without changing the electrical resistivity.
- Materials Research Laboratory and the Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106 (United States)
- Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112 (United States)
- Publication Date:
- OSTI Identifier:
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
- Country of Publication:
- United States
- 36 MATERIALS SCIENCE; ATOMS; ELECTRIC CONDUCTIVITY; MICROSTRUCTURE; PERFORMANCE; THERMAL CONDUCTIVITY; THERMOELECTRIC MATERIALS