TOSSPB: Thermoelectric optimization based on scattering-dependent single-parabolic band model

Thermoelectric materials can contribute to the energy generation by converting thermal into electrical energy. However, current thermoelectrics exhibit low efficiency due to their complex intertwined electrical and thermal properties. Diverse first-principles (based on density functional theory [DFT]) and experimental (based on the single parabolic band [SPB] model) optimization strategies have been explored. However, DFT calculations are limited to simple compounds due to their high computational cost and the SPB model commonly assumes that the electron transport is limited by acoustic phonons. Recent studies, however, revealed that other scattering mechanisms can also be dominant in high-performance thermoelectric materials. Here, a graphical user interface (GUI) is presented, and it allows to optimize the thermoelectric performance based on a scattering-dependent single parabolic band model, TOSSPB. In addition to acoustic deformation potential scattering, polar optical phonon and (screened and non-screened) ionized impurity scattering are included. The GUI indicates that the optimization strategies are strongly dependent on the scattering mechanism which can be obtained using the experimental Hall data and Seebeck coefficient of multiple samples. TOSSPB was tested on the thermoelectric properties of PbTe and SnSe. While the electronic properties of PbTe can be limited by acoustic phonons or polar optical phonons, ionized impurity is most likely the dominant scattering mechanism in hole-doped SnSe as recently predicted. By providing understanding for the scattering mechanism, TOSSPB can tailor the optimization strategies in a wide range of thermoelectric materials accelerating the discovery of high-performance thermoelectrics.