Enhanced Thermoelectric Performance Achieved in SnTe via the Synergy of Valence Band Regulation and Fermi Level Modulation

Xu，Xiao1,2; Cui，Juan1; Fu，Liangwei1; Huang，Yi1; Yu，Yong1; Zhou，Yi1; Wu，Di3; He，Jiaqing1

2021-10-27

10.1021/acsami.1c15595

ACS Applied Materials & Interfaces   影响因子和分区

1944-8244

1944-8252

SnTe is deemed a promising mid-temperature thermoelectric material for low toxicity, low cost, and decent performance. Sole doping/alloying on Sn sites was reported to result in either modified band alignment or reduced lattice thermal conductivity, thus contributing to an enhanced overall thermoelectric figure of merit. However, this strategy alone is always unable to take full use of the material's advantage, especially considering that it simultaneously pushes the hole concentration off the optimal range. In this work, we adopted a two-step approach to optimize the thermoelectric performance of SnTe in order to overcome the limitation. First, Mn was alloyed into Sn sites to increase the density of state effective mass of SnTe by regulating the valence bands; the Fermi level was further regulated by iodine doping, guided by a refined two-band model. Additionally, the lattice thermal conductivity was also suppressed by the microstructure optimizing via Mn doping and additional phonon scattering at ITe mass/strain fluctuation. As a result, a high ZT of 1.4 at 873 K was achieved for Sn0.91Mn0.09Te0.99I0.01. This study provides a way to refine the single doping stratagem used in other thermoelectric materials.

band convergence carrier optimization SnTe thermoelectrics two-band model

EI ; SCI

英语

第一 ; 通讯

National Natural Science Foundation of China[51802146,11934007,11874194,51632005] ; leading talents of the Guangdong Province Program[00201517] ; Science, Technology, and Innovation Committee Foundation of Shenzhen["KQTD2016022619565991","JCYJ20200109141205978","ZDSYS20141118160434515"]

Science & Technology - Other Topics ; Materials Science

Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary

WOS:000713052700041

AMER CHEMICAL SOC

20214611145356

Crystal lattices ; Fermi level ; Hole concentration ; IV-VI semiconductors ; Thermal conductivity ; Thermoelectric equipment ; Thermoelectricity ; Tin ; Tin compounds ; Valence bands

Tin and Alloys:546.2 ; Thermoelectric Energy:615.4 ; Thermodynamics:641.1 ; Electricity: Basic Concepts and Phenomena:701.1 ; Semiconducting Materials:712.1 ; Atomic and Molecular Physics:931.3 ; Crystal Lattice:933.1.1

2-s2.0-85118777212

Scopus

1.Department of Physics,Southern University of Science and Technology,Shenzhen,518055,China
2.Academy for Advanced Interdisciplinary Studies,Southern University of Science and Technology,Shenzhen,518055,China
3.School of Materials Science and Engineering,Shaanxi Normal University,Xi'an,710119,China

Xu，Xiao,Cui，Juan,Fu，Liangwei,et al. Enhanced Thermoelectric Performance Achieved in SnTe via the Synergy of Valence Band Regulation and Fermi Level Modulation[J]. ACS Applied Materials & Interfaces,2021,13(42):50037-50045.

Xu，Xiao.,Cui，Juan.,Fu，Liangwei.,Huang，Yi.,Yu，Yong.,...&He，Jiaqing.(2021).Enhanced Thermoelectric Performance Achieved in SnTe via the Synergy of Valence Band Regulation and Fermi Level Modulation.ACS Applied Materials & Interfaces,13(42),50037-50045.

Xu，Xiao,et al."Enhanced Thermoelectric Performance Achieved in SnTe via the Synergy of Valence Band Regulation and Fermi Level Modulation".ACS Applied Materials & Interfaces 13.42(2021):50037-50045.