Szczegóły publikacji
Opis bibliograficzny
Engineering electronic structure and lattice dynamics to achieve enhanced thermoelectric performance of Mn−Sb co-doped GeTe / Ashutosh Kumar, Preeti Bhumla, Taras Parashchuk, Stanisław Baran, Saswata Bhattacharya, Krzysztof T. WOJCIECHOWSKI // Chemistry of Materials ; ISSN 0897-4756. — 2021 — vol. 33 iss. 10, s. 3611–3620. — Bibliogr. s. 3618–3620, Abstr. — Publikacja dostępna online od: 2021-05-11
Autorzy (6)
- Kumar Ashutosh
- Bhumla Preeti
- Parashchuk Taras
- Baran Stanisław
- Bhattacharya Saswata
- AGHWojciechowski Krzysztof Tomasz
Dane bibliometryczne
| ID BaDAP | 134585 |
|---|---|
| Data dodania do BaDAP | 2021-06-14 |
| Tekst źródłowy | URL |
| DOI | 10.1021/acs.chemmater.1c00331 |
| Rok publikacji | 2021 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Czasopismo/seria | Chemistry of Materials |
Abstract
GeTe, as a p-type semiconductor, has been intensively studied in recent years as a promising lead-free mid-temperature-range thermoelectric (TE) material. Herein, we report an improved energy conversion efficiency (η) using a two-step TE properties optimization in Mn–Sb co-doped GeTe by engineering electronic structure and lattice dynamics. Mn–Sb co-doping enhances the TE properties of GeTe, as evidenced from both experiments and first-principles-based theoretical calculations. The density functional theory (DFT) calculations indicate that Mn–Sb co-doping improves the band convergence and optimizes the Fermi level position. This in turn helps in enhancing the Seebeck coefficient (α). As a result of the optimized Seebeck coefficient and electrical conductivity (σ), an enhanced power factor (α2σ) is obtained for the Mn–Sb co-doped system. Moreover, a significant reduction in the phonon (lattice) thermal conductivity (κph ∼ 0.753 W/mK) at 748 K is observed for Ge0.87Mn0.05Sb0.08Te, attributed to the point-defect scattering and reduced phonon group velocity. The synergistic improvement in α and reduction in κph result in a maximum figure-of-merit (zT) of 1.67 at 773 K, with an average zT (zTav) of ∼ 0.9 for Ge0.87Mn0.05Sb0.08Te over a temperature range of 300–773 K, leading to an η of ∼12.7%.
