Development of high performance thermoelectric materials using information about fine electronic structure and phonon dispersions

在这项研究中，我们利用关于电子结构和声子色散的详细信息，构建了高性能热电材料的指导原则，并开发了新的热电材料。第一性原理计算的结果表明，一些选定的合金具有适合于实际热电材料的电子结构。实验证实了它们具有较大的Seebeck系数和金属导电性。我们还利用原子簇计算发现，一些重元素不会引起任何电学性质的变化，但当它们部分替代组成元素时，可能会导致晶格热导率的显著降低。这一趋势在实验上得到了证实，并由此开发出了可在500K左右使用的廉价、环境友好的热电材料。

In this study, we constructed a guiding principle for the high-performance thermoelectric materials using detailed information about electronic structure and phonon dispersions, and developed new thermoelectric materials.As a result of first principles calculations, we found that some of the selected alloys possess a electronic structure suitable for practical thermoelectric materials. Their possession of large of Seebeck coefficient and metallic electrical conduction was confirmed experimentally.We also found, by using cluster calculation, that some of the heavy elements do not cause any variation in electrical properties but supposed to cause significant reduction in lattice thermal conductivity when they are partially substituted for the constituent elements. This tendency was confirmed experimentally, and the cheap, environmentally friendly thermoelectric materials usable at around 500 K were consequently developed.