Team achieves 30-fold enhancement of thermoelectric performance in polycrystalline tin selenide

https://phys.org/news/2022-03-team-fold-thermoelectric-polycrystalline-tin.html

"isovalent Te ion substitution increases σ and reduces κ, simultaneously... first-principles calculations to elucidate the mechanism underlying the improvement in ZT. The calculations showed that the large Te ion in SnSe formed weak Sn-Te bonds... Sn-Te bond is easily dissociated and a high density of Sn vacancies is formed in the structure, leading to a high hole concentration.... weak Sn-Te bonds reduce phonon frequency (frequency of lattice vibration) and enhance the phonon scattering, resulting in low κ"