Intentional Carrier Doping to Realize n-Type Conduction in Zintl Phases Eu5−yLayIn2.2Sb6

Materials

Yayun Gu¹  Xinxin Yang¹  Kai Guo¹  Jingtai Zhao¹  Jianwei Lin¹  Wanyu Lv¹ 

[1] School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;

关键词: Eu5In2Sb6;    Zintl phase;    n-type;    thermoelectric properties;   

DOI  :  10.3390/ma12020264

来源: DOAJ

【 摘 要 】

Due to the tunable electrical transport properties and lower thermal conductivity, Zintl phase compounds have been considered as a promising candidate for thermoelectric applications. Most Sb-based Zintl compounds exhibit essentially p-type conduction as result of the cation vacancy. Herein, n-type Zintl phases Eu5−yLayIn2.2Sb6 has been successfully synthesized via controlling the vacancy defect combined with intentional electron doping. Excess of In would occupy the vacancy while La doping enables the electron to be the major carrier at the measured temperate range, realizing the n-type conduction for Eu5−yLayIn2.2Sb6 (y ≥ 0.04). Meanwhile, the thermal conductivity of Eu5−yLayIn2.2Sb6 reduces from 0.90 W/mK to 0.72 W/mK at 583 K derived from the La doping-induced disorder. The maximum thermoelectric figure of merit zT = 0.13 was obtained. This work firstly realizes the n-type conduction in Eu5In2Sb6, which sheds light on the strategy to synthesize n-type Zintl thermoelectric materials and promotes the practical applications of Zintl thermoelectric devices.

【 授权许可】

Unknown