Realizing Excellent Structural and Thermoelectric Performance in Mg3Sb2-Based Alloys by Manipulating Mg Intrinsic Migration Kinetics with Interstitial Ni Doping

被引：7

作者：

Li, Zihao ^{[1
]}

Sun, Congli ^{[1
,2
]}

Li, Xiangyu ^{[1
]}

Ye, Xianfeng ^{[1
]}

Yang, Kangkang ^{[1
]}

Nie, Xiaolei ^{[1
]}

Zhao, Wenyu ^{[1
,3
]}

Zhang, Qingjie ^{[1
]}

机构：

[1] Wuhan Univ Technol, Int Sch Mat Sci & Engn, State Key Lab Adv Technol Mat Synth & Proc, Wuhan 430070, Peoples R China

[2] Wuhan Univ Technol, NRC Nanostruct Res Ctr, Wuhan 430070, Peoples R China

[3] Foshan Xianhu Lab, Adv Energy Sci & Technol Guangdong Lab, Xianhu 528000, Peoples R China

来源：

ACS APPLIED MATERIALS & INTERFACES | 2023年 / 15卷 / 19期

基金：

中国国家自然科学基金;

关键词：

N-type Mg3Sb2; room-temperature thermoelectric performance; Mg migration kinetics; thermal stability; charge density difference; ZINTL COMPOUNDS; ENHANCEMENT; SCATTERING; TRANSPORT;

D O I：

10.1021/acsami.3c02351

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

N-type Mg3Sb2 is attracting increasing focus for its outstanding room-temperature (RT) thermoelectric (TE) performance; however, achieving reliable n-type conduction remains challenging due to negatively charged Mg vacancies. Doping with compensation charges is generally used but does not fundamentally resolve the high intrinsic activity and easy formation of Mg vacancies. Herein, a robust structural and thermoelectric performance is obtained by manipulating Mg intrinsic migration activity by precisely incorporating Ni at the interstitial site. Density functional theory (DFT) indicates that a strong performance originates from a significant thermodynamic preference for Ni occupying the interstitial site across the complete Mg-poor to-rich window, which dramatically promotes the Mg migration barrier and kinetically immobilizes Mg. As a result, the detrimental vacancy associated ionized scattering is eliminated with a leading room-temperature ZT up to 0.85. This work reveals that interstitial occupation in Mg3Sb2-based materials is a novel approach promoting both structural and thermoelectric performance.

引用

页码：23447 / 23456

页数：10