Phys.org March 28, 2022
Tin selenide (SnSe) is known to exhibit a record high energy conversion (ZT) in its single crystal form. However, the performance deteriorates in practical polycrystals because of a low electronic conductivity (σ) and a high thermal conductivity (κ). Researchers in Japan
enhanced the ZT of polycrystalline SnSe by demonstrating a high σ and a low κ simultaneously by introducing tellurium (Te) ion into the structure of SnSe. The large-size Te ion in Sn(Se1−xTex) forms weak Sn-Te bonds, leading to the high-density formation of hole-donating Sn vacancies and the reduced phonon frequency and enhanced phonon scattering.
This result of their work—doping of large-size ions beyond the equilibrium limit—proposes a new idea for carrier doping and controlling thermal properties to enhance the ZT of polycrystalline SnSe…read more. Open Access TECHNICAL ARTICLE
Thermoelectric energy conversion. Credit: Tokyo Tech