Ag掺杂SnSe化合物的制备及热电性能  

Synthesis and Thermoelectric Properties of Ag-doped SnSe

作　　者：李松浩[1] 张忻[1] 刘洪亮[1] 郑亮[1] 张久兴[1,2] 

机构地区：[1]北京工业大学材料科学与工程学院新型功能材料教育部重点实验室,北京100124 [2]合肥工业大学材料科学与工程学院,合肥230009

出　　处：《无机材料学报》2016年第7期751-755,共5页Journal of Inorganic Materials

基　　金：北京市教育委员会科技计划面上项目(KM201510005001)~~

摘　　要：Sn Se是一种潜在的极具应用前景的热电材料。采用机械合金化结合放电等离子烧结的方法制备了Ag掺杂的Sn1-xAgxSe(0.005≤x≤0.03)多晶块体热电材料,并借助XRD、SEM、电热输运测试系统研究了其物相组成、微结构与电热输运性能。XRD分析结果表明,少量Ag(0.005≤x≤0.01)掺杂仍然能够成功制备出单相斜方结构Sn Se化合物,但随着Ag掺杂量的增加,基体中出现Sn Ag Se2第二相,且第二相含量逐渐增加。掺杂Ag大幅度提高了载流子浓度,从而使材料的综合电输运性能(功率因子)显著提高,当Ag掺杂量x=0.02时,功率因子提高至4.95×10-4 W/(m·K2),较未掺杂Sn Se样品提高了36%。尽管掺杂样品的热导率均有小幅升高,无量纲热电优值(ZT)仍获得一定改善。当Ag掺杂量x=0.02时,Sn0.98Ag0.02Se成分样品具有较高的热电优值,并在823 K附近达到最高值0.82。SnSe material is one of the most promising state-of-art thermoelectric materials. The polycrystalline Ag-doped Sn1-xAgxSe （0.005〈x〈0.03） bulks were prepared by mechanical alloying and spark plasma sintering technique, and the composition, microstructure and thermoelectric properties were systematically studied by XRD, SEM and thermoelectric performance measurement. XRD results show that single-phase orthorhombic SnSe-based compounds can be prepared with small amount of Ag-doping （0.005 ≤x≤ 0.01）, but with Ag doping amount increasing, small quantity of secondary phase, SnAgSe2, can be detected in the matrix. The carrier concentration and overall electrical properties （power factor） are significantly enhanced as a result of Ag doping. The power factor of Sn0.98Ag0.02Se increases up to 0.495× 10-3 W/（m·K2）, which is about 36% higher than that of SnSe material. Although the thermal conductivity increases slightly, the dimensionless figure of merit, ZT is still optimized for the Ag-doped samples. Sn0.98Ag0.02Se bulk shows optimal ZT value and the highest ZT of 0.82 is obtained at 823 K, which is the highest value reported for the polycrystalline SnSe-based thermoelectric materials.

关 键 词：SnSe AG掺杂 放电等离子烧结 热电性能 

分 类 号：TB34[一般工业技术—材料科学与工程]