Designing thermoelectric materials using inter-band electron-phonon scattering anomalies.

In recent years, efforts have intensified in looking at alternative paradigms and design strategies for discovering efficient thermoelectric materials, which can be used to capture waste heat as electrical energy. In a recent work [1], we found that inter-band electron-phonon scattering, that can occur in materials with intersecting heavy and light electron bands, leads to a strong variation of scattering lifetimes as a function of electron energy and can result in enhanced thermoelectric performance. When such a material is doped so that the chemical potential is near the heavy band, an anomalous peak in the thermoelectric power factor is observed. In this work, we perform a broad search for materials with such band characteristics. We performed detailed first-principles electron-phonon transport calculations for several candidate materials to investigate the potential for increased thermoelectric performance based on this light-heavy band mechanism.