Carrier–phonon decoupling via annealing enhances thermoelectric performance of Bi2(Te,Se)3
Abstract
Thermoelectric cooling based on the Peltier effect requires high-performance materials near room temperature. While Bi2Te3 remains the most viable commercial thermoelectric material, n-type Bi2Te3−xSex (BTS) lags behind its p-type counterpart due to intrinsic anisotropy. In this work, Bi2Te2.6Se0.4 synthesized by melting-hot pressing followed by 100 h annealing (MT-HP-AN) at 723 K exhibits markedly improved performance. Annealing introduces cation vacancies via Te(Se) volatilization, lowering carrier density and enhancing mobility, while simultaneously increasing phonon scattering. A peak ZT of 1.06 at 373 K and an average ZT of 0.99 at 300–423 K are achieved. This MT-HP-AN approach offers a simple yet effective strategy to decouple carrier and phonon transport, advancing the potential of n-type BTS for thermoelectric cooling applications.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (7)
Xinxiu Cheng
State Key Laboratory of Porous Metal Materials, School of Materials Science and Engineering, Xi'an Jiaotong University 1 , Xi'an 710049,
Liqing Xu
School of Materials and Energy, University of Electronic Science and Technology of China 2 , Chengdu 611731,
Zhibin Gao
State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi’an Jiaotong University 1 , Xi’an 710049,
Wei Liu
Zhanxiang Yin
School of Materials and Energy, University of Electronic Science and Technology of China 2 , Chengdu 611731,
Xiangdong Ding
Yu Xiao