High near-room temperature figure of merit of n-type Bi2GeTe4-based thermoelectric materials via a stepwise optimization of carrier concentration
Article
Article Title | High near-room temperature figure of merit of n-type Bi2GeTe4-based thermoelectric materials via a stepwise optimization of carrier concentration |
---|---|
ERA Journal ID | 3854 |
Article Category | Article |
Authors | Yin, Liang-Cao (Author), Liu, Wei-Di (Author), Shi, Xiao-Lei (Author), Gao, Han (Author), Li, Meng (Author), Wang, De-Zhuang (Author), Wu, Hao (Author), Kou, Liangzhi (Author), Guo, Haizhong (Author), Wang, Yifeng (Author), Liu, Qingfeng (Author) and Chen, Zhi-Gang (Author) |
Journal Title | Chemical Engineering Journal |
Journal Citation | 433 (Part 3), pp. 1-8 |
Article Number | 133775 |
Number of Pages | 8 |
Year | 2022 |
Publisher | Elsevier |
Place of Publication | Netherlands |
ISSN | 1385-8947 |
1873-3212 | |
Digital Object Identifier (DOI) | https://doi.org/10.1016/j.cej.2021.133775 |
Web Address (URL) | https://www.sciencedirect.com/science/article/pii/S1385894721053493 |
Abstract | Bi2GeTe4 is a promising near room-temperature thermoelectric candidate with a low lattice thermal conductivity. Carrier concentration of intrinsic Bi2GeTe4 changes dramatically with tiny Ge content adjustment, leading to a challenge in carrier concentration optimization. To overcome this challenge, we firstly introduce excessive Ge into Bi2GeTe4 to shift the Fermi level deep into the conduction band and transfer Bi2GeTe4 into a highly degenerate n-type semiconductor. Secondly, the embedded p-type Bi2Ge2Te5 secondary phase induces further optimization of the Fermi level and carrier concentration. Finally, the power factor of the as-synthesized Bi2GeTe4-based material is significantly increased from ∼ 0.08 μW cm−1 K−2 to ∼ 4.2 μW cm−1 K−2 at 423 K when increasing the nominal Ge content (x) of Bi2GexTe4 from 1 to 1.45. Correspondingly, a high figure-of-merit of ∼ 0.22 at 423 K is achieved in Bi2GeTe4-based thermoelectric materials. This result indicates our viable stepwise strategy can be used to optimize carrier concentration and achieve high thermoelectric performance of the n-type Bi2GeTe4. |
Keywords | Bi2GeTe4; Thermoelectric; Carrier concentration; Optimization; zT |
ANZSRC Field of Research 2020 | 401605. Functional materials |
Public Notes | Files associated with this item cannot be displayed due to copyright restrictions. |
Byline Affiliations | Nanjing Tech University, China |
Centre for Future Materials | |
Zhengzhou University, China | |
University of Queensland | |
Queensland University of Technology | |
Institution of Origin | University of Southern Queensland |
https://research.usq.edu.au/item/q6xy0/high-near-room-temperature-figure-of-merit-of-n-type-bi2gete4-based-thermoelectric-materials-via-a-stepwise-optimization-of-carrier-concentration
Download files
100
total views64
total downloads0
views this month0
downloads this month