Enhanced Thermoelectric Performance of Mg-Doped AgSbTe2 by Inhibiting the Formation of Ag2Te,ACS Applied Materials & Interfaces

当前位置： X-MOL 学术 › ACS Appl. Mater. Interfaces › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Enhanced Thermoelectric Performance of Mg-Doped AgSbTe2 by Inhibiting the Formation of Ag2Te
ACS Applied Materials & Interfaces ( IF 8.3 ) Pub Date : 2023-02-07 , DOI: 10.1021/acsami.2c22930
Rui Du _{1,

2} , Guangbiao Zhang _{1,

2} , Min Hao _{1,

2} , Xiaowei Xuan _{1,

2} , Panpan Peng _{1,

2} , Pengya Fan _{1,

2} , Haotian Si _{1,

2} , Gui Yang ₃ , Chao Wang _{1,

2}

Affiliation

The existence of Ag₂Te has always been an obstacle for p-type thermoelectric material AgSbTe₂ to improve its thermoelectric performance. In this work, AgSb_1–xMg_xTe₂ samples are synthesized by melting-slow-cooling and then spark plasma sintering (SPS). Through increasing the solubility of Ag₂Te in the AgSbTe₂ matrix by Mg doping, the formation of Ag₂Te is inhibited. Density functional theory calculations confirm more valence bands are involved in electrical transport due to Mg doping. Therefore, the electrical conductivity of AgSb_1–xMg_xTe₂ samples has been greatly improved due to the reduction of Ag₂Te with n-type electrical conductivity. Moreover, the downward trend of ZT, which is caused by the structural transition of Ag₂Te at about 418 K, disappears. Meanwhile, lattice defects form in the AgSb_0.98Mg_0.02Te₂ sample, and Mg doping improves the configurational entropy change, resulting in a decrease in lattice thermal conductivity over the entire temperature range of measurement. Finally, a high ZT value of 1.31 at 523 K is achieved for the AgSb_0.98Mg_0.02Te₂ sample. This study demonstrates that Mg doping can effectively improve AgSbTe₂ thermoelectric performance by inhibiting the formation of the Ag₂Te impurity phase.

中文翻译：

通过抑制 Ag2Te 的形成增强掺镁 AgSbTe2 的热电性能

Ag ₂ Te的存在一直是p型热电材料AgSbTe ₂提高热电性能的障碍。在这项工作中，AgSb _{1– x} Mg _x Te ₂样品通过熔化-缓慢冷却然后放电等离子烧结（SPS）合成。通过Mg掺杂增加Ag ₂ Te在AgSbTe ₂基体中的溶解度，抑制Ag ₂ Te的形成。密度泛函理论计算证实，由于镁掺杂，更多的价带参与了电传输。因此，由于具有n型导电性的Ag ₂ Te被还原，AgSb _{1– x} Mg _x Te ₂样品的电导率得到了极大的提高。此外，由Ag ₂ Te在418K左右的结构转变引起的ZT下降趋势也消失了。同时，AgSb _0.98 Mg _0.02 Te ₂样品中形成晶格缺陷，Mg掺杂改善了构型熵变，导致整个测量温度范围内晶格热导率下降。最后，AgSb _0.98 Mg _0.02 Te ₂样品在523 K 时获得了1.31 的高ZT 值。研究表明，Mg掺杂可以通过抑制Ag ₂ Te杂质相的形成，有效提高AgSbTe ₂热电性能。

更新日期：2023-02-07

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南