三元 PbBi2S4 是一种具有本征低晶格热导率的潜力热电材料，但低的电传输性能制约了其热电性能。 本工作 利 用 Bridgman 法 制 备 了 高 质 量 的 三 元 PbBi2S4 晶 体 铸 锭 ， 由 于 减 少 晶 界 密 度 ， 降 低 晶 界 对 载 流 子 传 输 阻 碍 ，电 传输性能大幅度提升。 通过优化生长条件获得不同质量的三元 PbBi2S4 晶体铸锭，最优加权载流子迁移率从 多晶中 15 cm2 /(V·s)提升到 56 cm2 /(V·s)，使三元 PbBi2S4 晶体铸锭的最大电导率和功率因子分别达到 1 049 S/cm和 4.6 μW/(cm·K2 )，相比多晶 PbBi2S4 样品分别提高了 850%和 ~64%。 最终，PbBi2S4 晶体铸锭的最大 ZT 值在 773 K 温 度下达到 0.61。 结果表明，通过凝固生长高质量晶体铸锭能显著优化三元 PbBi2S4 化合物全温区热电性能。

Ternary PbBi2S4 is a potential thermoelectric material with intrinsically low lattice thermal conductivity, but the low electrical transport properties limit its thermoelectric properties. In this work, high-quality ternary PbBi2S4 crystal ingots were prepared by the Bridgman method. By reducing the grain boundary density to reduce the carrier transport barrier, the electrical transport properties greatly improved. By optimizing the growth conditions, ternary PbBi2S4 crystal ingots of different qualities were obtained. The optimal weighted mobility increases from 15 cm2 /(V·s) in the polycrystal to 56 cm2 /(V·s), and the maximum electrical conductivity and power factor of the ternary PbBi2S4 crystal ingot reach 1 049 S/cm and 4.6 μW/(cm·K2 ), respectively. Compared with those of the polycrystalline PbBi2S4 sample, the increases are 850% and ~64%, respectively. Finally, the maximum ZT value in the PbBi2S4 crystal ingot reaches 0.61 at 773 K. The results show that the solidification growth of high-quality crystal ingots can significantly optimize the full-temperature thermoelectric properties of the ternary PbBi2S4 compound.