Comparative ab initio study of the electronic structure and thermoelectric properties of tin selenide with electron and hole conductivity
Physica B: Condensed Matter, vol.695, 2024 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 695
- Publication Date: 2024
- Doi Number: 10.1016/j.physb.2024.416529
- Journal Name: Physica B: Condensed Matter
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
- Keywords: Boltzmann-onzager theory, Figure-of-merit, First-principles calculations, PAW method, Power function, Tin selenide
- Open Archive Collection: Article
- Azerbaijan State University of Economics (UNEC) Affiliated: Yes
Abstract
Ab initio calculations of the electronic structure and thermoelectric characteristics of low- and high-temperature phases of tin selenide, SnSe, with electronic and hole conductivity have been performed. It is shown that the calculations of thermoelectric properties on the basis of the Boltzmann-Onzager theory with consideration of carrier scattering on optical phonons lead to results in good agreement with experimental data. At temperatures below 600 K the modeling correctly reproduces the increased values of the figure-of-merit of electron-doped SnSe in comparison with almost stoichiometric or hole-doped selenide calculations. We explain anomalously high figure-of-merit values of the non-doped selenide at T > 600 K by the hole concentration increase due to oxidation of SnSe or the appearance of vacancies in the tin sublattice. For all the considered variants, i.e. for electron-doped low-temperature and high-temperature phases and low-temperature hole-doped phase, the modeling predicts the absence of figure-of-merit increase at exceeding some limiting concentration of current carriers.