Sb掺杂对Mg_2Si基化合物热电性能的影响(英文)

Effect of Sb-Doping on the Thermoelectric Properties of Mg_2Si Based Compounds

采用感应熔炼和真空热压的方法制备了Sb掺杂和未掺杂的Mg2Si基热电材料。研究了Sb掺杂对Mg2Si基热电材料的结构以及热电特性的影响。结果表明:通过Sb掺杂使得载流子浓度从3.07×1019cm-3增加到1.25×1020cm-3,电子有效质量也相应增加。测试了从室温到800K下试样的Seebeck系数,电导率和热导率。结果显示,0.3at%Sb掺杂使得电导率得到显著增加,在783K时,ZT值达到0.7。

Sb-doped and undoped Mg2Si thermoelectric materials were prepared by melting followed by hot-pressing. Effects of doped Sb on the structures and thermoelectric properties of the Mg2Si compounds were investigated. The carrier concentration increases from 3.07× 10^19 cm^-3 to 1.25× 10^20 cm^-3, and the electron effective mass increases by Sb doping. The Seebeck coefficient, the electrical conductivity and the thermal conductivity were measured from room temperature to 800 K. It is shown that the electrical conductivity increases dramatically due to the doping of 0.3 at% Sb, resulting in a higher dimensionless figure of merit of 0.7 at 783 K.