Enhanced electrical transport performance through cation site doping in Y-doped Mg_(3.2)Sb_(2)  

作　　者：Yang Wang Xin Zhang Yanqin Liu Yangzhong Wang Hongliang Liu Jiuxing Zhang 

机构地区：[1]College of Materials Science and Engineering,Beijing University of Technology,Key Laboratory of Advanced Functional Materials,Ministry of Education,Beijing,100124,China [2]School of Materials Science and Engineering,Hefei University of Technology,Hefei,230009,China

出　　处：《Journal of Materiomics》2020年第1期216-223,共8页无机材料学学报（英文）

基　　金：supported by National Natural Science Foundation of China,China(Grant Nos.51371010,51572066 and 50801002);Beijing Municipal Natural Science Foundation,China(Grant No.2112007);the Fundamental Research Funds for the Central Universities,China(PXM2019-014204-500032).

摘　　要：Mg_(3)Sb_(2)-based alloys are promising thermoelectric materials through n-type doping in Mg-rich growth conditions to overcome their intrinsic p-type behavior.First principle calculations are employed to investigate the dopant formation energy and electronic structures of Y-doped Mg_(3)Sb_(2).Results indicate that the Y atom is more favorable for substitution at the cation site.Simultaneously,the flattened band structure and increased density of state near the Fermi level of Y-doped Mg_(3)Sb_(2) indicate an enhanced electronic transport performance.The carrier concentration rises to 5.31×10^(19) cm^(-3) at room temperature,resulting in a significant increased power factor for Mg_(3.17)Y_(0.03)Sb_(2).The available optimization of electrical transport contributes to excellent thermoelectric performance,and a peak ZT~0.83 at 773 K was achieved for Y concentration x=0.03 in Mg_(3.2-x)Y_(x)Sb_(2).This work provides an alternative measure for optimizing the thermoelectric performance of n-type Mg_(3)Sb_(2) alloys by cation site doping.

关 键 词：First principle calculations n-type Mg_(3)Sb_(2) Y doping Thermoelectric performance 

分 类 号：TG14[一般工业技术—材料科学与工程]