PHENOMENOLOGICAL APPROACH TO IDENTIFYING NEW THERMOELECTRIC MATERIALS

摘要

Identification of potentially good thermoelectric compounds/alloys from a knowledge of their constitute elements provides a very useful initial procedure in the search for new thermoelectric materials. Research efforts can then be focused on promising areas where good thermoelectric materials are likely to be found. Phenomenological approaches are employed, aided by modern fast computers and an extensive materials databases previously unavailable, in identifying possible correlation between the thermoelectric properties and various properties of the material's constituent elements. The results show that the electrical power factor exhibits a behaviour which depends on the electronegativity difference, while the thermal conductivity relates to the atomic radii, eletronegativity difference and atomic weight of the constitute elements. As a result, a "thermoelectric properties diagram" has been constructed in an attempt to predict new materials with potentially high thermoelectric figure-of-merit. Preliminary results show that a clear localisation of thermoelectric materials is obtained in this diagram for both binary and ternary semiconductor compounds. It is concluded that the procedure developed may enable potentially good thermoelectric materials to be identified.