Abstract
The feasibility of using Bi2Te3-based alloys in low-grade heat thermoelectric power generation has been intensively investigated via a substitutional doping approach over the last decade. However, the comprehensive and quantitative understanding of the electronic and thermal transport parameters of doped Bi2Te3-based alloys including their carrier concentration (nc), carrier mobility (μHall), density of state (DOS) effective mass (md∗), and electronic (κele), lattice (κlat), and bipolar thermal (κbp) conductivities is still elusive. The understanding of these parameters is a prerequisite for designing the modules for real-time applications. In this study, we investigated the effect of Pb, Ag, and Cu doping on the thermoelectric transport parameters of p-type Bi0.52Sb1.48Te3 (BST) both theoretically and experimentally. The thermoelectric transport properties of BST and their temperature dependences could be systematically tuned in a low-temperature range by controlled doping of Pb, Ag, and Cu mainly because of the increased concentration of the majority hole carriers. In addition, a zT value of 1 could be obtained over the wide temperature range of 300–400 K by optimizing the doping elements and contents because of the synergetic effect of the suppression of bipolar conduction at higher temperatures and the gradual increase in md∗ with the doping content at nc < 1020 cm−3.
Original language | English |
---|---|
Pages (from-to) | 593-602 |
Number of pages | 10 |
Journal | Journal of Alloys and Compounds |
Volume | 772 |
DOIs | |
Publication status | Published - 2019 Jan 25 |
Bibliographical note
Funding Information:This work was supported by the National Research Foundation of Korea (NRF) Grant (2017R1A2A1A17069528) funded by the Korea government (MSIT). KK is grateful for financial support from Yonsei University Research Fund (Post Doc. Researcher Supporting Program) of 2017 (project no.: 2017-12-0039).
Funding Information:
This work was supported by the National Research Foundation of Korea ( NRF ) Grant ( 2017R1A2A1A17069528 ) funded by the Korea government ( MSIT ). KK is grateful for financial support from Yonsei University Research Fund (Post Doc. Researcher Supporting Program) of 2017 (project no.: 2017-12-0039 ).
Publisher Copyright:
© 2018
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry