Thermoelectric devices having both high conversion efficiency and high power density (“double-high”) are in high demand for power-generation applications. Conventional research approaches on thermoelectric devices primarily focus on the realization of high conversion efficiency, while the power density is often overlooked. We propose a device-to-material design strategy for “double-high” thermoelectric modules, which integrates multiple criteria including matching thermal conductivities in p- and n-type thermoelectric materials, optimizing topologic structures of modules, and minimizing interfacial resistance. According to the thermal-conductivity matching criterion, the n-type Zr_0.5Hf_0.5NiSn_0.97Sb_0.03 half-Heusler alloy, which possesses an excellent power factor but slightly lower zT, is adopted as the partner of the p-type Nb_0.86Hf_0.14FeSb alloy for realizing a double-high thermoelectric module. The newly developed 8-pair module achieves a maximum conversion efficiency of 10.5% and power density of 3.1 Wcm⁻² at a temperature difference of 680 K, simultaneously breaking both records in a single-stage module.

具有高转换效率和高功率密度（“双高”）的热电器件对发电应用有很高的要求。关于热电设备的常规研究方法主要集中在高转换效率的实现上，而功率密度却常常被忽略。我们为“双高”热电模块提出了一种设备到材料的设计策略，该策略整合了多个标准，包括在p型和n型热电材料中匹配热导率，优化模块的拓扑结构以及最小化界面电阻。根据热导率匹配准则，n型Zr _0.5 Hf _0.5 NiSn _0.97 Sb _0.03p型Nb _0.86 Hf _0.14 FeSb合金的搭档采用功率因数优异但zT稍低的Half-Heusler合金，以实现双高热电模块。新开发的8对模块在680 K的温差下实现了10.5％的最大转换效率和3.1 Wcm ^-2的功率密度，同时打破了单级模块的两个记录。