Abstract

Materials best-suited for direct application exhibit a high thermoelectric figure of merit (ZT) close to unity, from room temperature to ∼ 400 K. In this work, we investigated the thermoelectric behavior of Ag₂Se, and a sulfur substituted Ag₂Se system, i.e. Ag₂S_0.2Se_0.8 and Ag₂S_0.4Se_0.6 , in the temperature range of 300 K to 500 K. With strong anharmonic lattice vibration and semiconducting electronic structure, these materials showed thermal conductivity less than 1 W m⁻¹ K⁻¹, electrical resistivity ∼ 1 mΩ cm, together with moderate Seebeck coefficient values of ∼ − 140 μV K⁻¹ in the low-temperature phase. We were able to achieve ZT equal to unity in a wide temperature range of 350–400 K, with a maximum value of ZT = 1.08 at 350 K for the Ag₂S_0.4Se_0.6 material.

中文翻译：

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Ag 2 S x Se 1-x（x = 0.0、0.2和0.4）的热电性能研究

抽象的

最适合直接应用的材料在从室温到约400 K的温度下都具有接近于1的高热电品质因数（ZT）。在这项工作中，我们研究了Ag ₂ Se和硫取代的Ag ₂ Se的热电行为。在300 K至500 K的温度范围内形成Ag ₂ S _0.2 Se _0.8和Ag ₂ S _0.4 Se _0.6体系。这些材料具有强的非谐晶格振动和半导体电子结构，导热率小于1 W m ^-1  K ^-1电阻率约为1mΩcm，在低温阶段的塞贝克系数约为 -140μV K ^-1。我们能够实现ZT等于单位在宽的温度范围350-400的K，具有的最大值ZT 在350 K = 1.08银₂小号_0.4硒_0.6的材料。