4. Thermoelectric materials: state of the art and new developments

4.1 Materials selection

A global mathematical analysis of the dependence of the ZT factor on temperature and charge carrier concentration is complex, as it requires precise knowledge of the energy spectra of phonons and charge carriers, as well as their scattering mechanisms.

Among the approaches that have been developed to deal with transport phenomena in materials, the approach based on the Boltzmann equation has been widely used to describe transport phenomena in metals and semiconductors. Notably, in the 1950s, Ioffe