Here, a p-type polycrystalline SnSe integrated with PbSe quantum dots is fabricated by an in situ magnetic field-assisted hydrothermal route. The decrease of the critical nucleation free energy and increase of homogeneous nucleation rate lead to the formation of PbSe quantum dots under high magnetic field. The enhanced density of states due to PbSe quantum dots causes significantly enhanced Seebeck coefficients and power factor. A large integral area of power factor over the full temperature range is optimized. The lattice strain induced by dislocations and stacking faults shortens the phonon relaxation time, leading to an ultralow lattice thermal conductivity (0.32 W m⁻¹ K⁻¹ at 873 K perpendicular to the pressing direction). Consequently, these electronic and thermal effects contribute to a high ZT of ∼1.9 at 873 K and an outstanding average ZT of 0.71 in polycrystalline SnSe. The combination of introducing PbSe quantum dots functional units and manipulating lattice strain provides a new perspective for designing high performance thermoelectric devices.

在这里，通过原位磁场辅助水热路线制造了与 PbSe 量子点集成的 p 型多晶 SnSe 。临界成核自由能的降低和均匀成核率的增加导致在高磁场下形成 PbSe 量子点。由于 PbSe 量子点而导致的态密度增强导致塞贝克系数和功率因数显着增强。优化了整个温度范围内功率因数的大积分区域。位错和堆垛层错引起的晶格应变缩短了声子弛豫时间，导致超低晶格热导率（0.32 W m ^-1  K ^-1在垂直于加压方向的 873 K 处）。因此，这些电子和热效应有助于在 873 K 下实现 ~1.9的高ZT和多晶 SnSe 中 0.71的出色平均ZT。引入 PbSe 量子点功能单元和操纵晶格应变的结合为设计高性能热电器件提供了新的视角。