The diamond-like compound Cu3PSe4 with low lattice thermal conductivity is deemed to be a promising thermoelectric material, which can directly convert waste heat into electricity or vice versa with no moving parts and greenhouse emissions. However, its performance is limited by its low electrical conductivity. In this study, we report an effective method to enhance thermoelectric performance of Cu3PSe4 by defect engineering. It is found that the carrier concentrations of Cu3−xPSe4 (x = 0, 0.03, 0.06, 0.09, 0.12) compounds are increased by two orders of magnitude as x > 0.03, from 1 × 1017 to 1 × 1019 cm−3. Combined with the intrinsically low lattice thermal conductivities and enhanced electrical transport performance, a maximum zT value of 0.62 is obtained at 727 K for x = 0.12 sample, revealing that Cu defect regulation can be an effective method for enhancing thermoelectric performance of Cu3PSe4.

中文翻译：

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通过缺陷工程增强三元化合物 Cu3PSe4 的热电性能

具有低晶格热导率的类金刚石化合物 Cu3PSe4 被认为是一种很有前途的热电材料，它可以将废热直接转化为电能，反之亦然，没有移动部件和温室气体排放。然而，其性能受到其低导电性的限制。在这项研究中，我们报告了一种通过缺陷工程提高 Cu3PSe4 热电性能的有效方法。发现 Cu3-xPSe4 (x = 0, 0.03, 0.06, 0.09, 0.12) 化合物的载流子浓度随着 x > 0.03 增加两个数量级，从 1 × 1017 到 1 × 1019 cm-3。结合固有的低晶格热导率和增强的电传输性能，x = 0.12 样品在 727 K 时获得的最大 zT 值为 0.62，