n-Type polycrystalline SnSe with Ti, Pb co-doping was synthesized by combining mechanical alloying (MA) with spark plasma sintering (SPS). It is revealed that Ti is an effective cationic dopant to convert SnSe from a p-type to an n-type semiconductor, and the thermoelectric performance of the Ti-doped SnSe is also improved in comparison with the pristine sample due to an enhanced power factor. Furthermore, after further Pb doping, an obviously improved electrical conductivity together with a moderate Seebeck coefficient can be achieved, which results in an improvement of the power factor with a maximum value of 300 μW m⁻¹ K⁻² at 773 K. Meanwhile, the lattice thermal conductivity is significantly reduced because of the enhanced phonon scattering owing to the mass and strain fluctuations. Therefore, a final ZT value of 0.4 was obtained for composition of Sn_0.74Pb_0.20Ti_0.06Se at 773 K, which is a conservative value for n-type SnSe with cationic dopant prepared by the simple preparation process of MA and SPS.

中文翻译：

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n型Ti，Pb共掺杂SnSe热电性能的优化

通过将机械合金化（MA）与火花等离子体烧结（SPS）相结合，合成了具有Ti，Pb共掺杂的n型多晶SnSe。揭示了Ti是将SnSe从p型半导体转换为n型半导体的有效阳离子掺杂剂，并且由于提高了功率因数，与原始样品相比，Ti掺杂的SnSe的热电性能也得到了改善。 。此外，在进一步掺杂Pb之后，可以实现明显改善的电导率以及适度的塞贝克系数，从而提高了功率因数，最大值为300μWm ^-1 K ^-2同时，在773 K时。由于质量和应变的波动，声子散射增强，晶格热导率大大降低。因此，对于773 K处的Sn _0.74 Pb _0.20 Ti _0.06 Se的组成，最终的ZT值为0.4 ，这是通过MA和SPS的简单制备方法制备的带有阳离子掺杂剂的n型SnSe的保守值。