Advanced study of the electronic and thermoelectric properties of AEMSe compounds under compression and tensile strain†
Abstract
This paper reports an in-depth investigation of the electrical and thermoelectric properties of alkaline earth metal selenide (AEMSe) compounds, such as BeSe, CaSe, SrSe, and BaSe, under various compression and tensile strain conditions (−5%, 0%, and 5%). The compounds under consideration are in the cubic FCC phases; BeSe crystallizes into the ZnS phase, and the others crystallize into the NaCl phase. The energy band structures were calculated using the ONCV pseudopotentials, the HSE hybrid functionals, and the Wannier interpolation method. Using the Gibbs2 tool, the lattice thermal conductivity of unstrained materials was computed. Thermoelectric parameters such as the Seebeck coefficient, thermal conductivity, electrical conductivity, and figure of merit (ZT) were calculated, revealing that BaSe is a highly promising thermoelectric material. This comprehensive study sheds light on the compositional dependency of AEMSe compounds and identifies prospective regions for thermoelectric applications. Specifically, BaSe emerges as a highly promising thermoelectric material with a peak ZT of 1.51 under unstrained p-type doping at 800 K, demonstrating its significant potential for energy conversion technologies.