Hou Zhenghao, Wang Dongyang, Wang Jinfeng, Wang Guangtao, Huang Zhiwei, Zhao Li-Dong
School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
School of Physics, Henan Normal University, Xinxiang 453007, China.
Research (Wash D C). 2020 Dec 3;2020:4084532. doi: 10.34133/2020/4084532. eCollection 2020.
PbS is a latent substitute of PbTe thermoelectric materials, which is on account of its superiority in low cost and earth abundance. Here, the thermoelectric transport properties of -type PbS by doping alkali metals (Na and Li) are investigated and it is verified that Li is a more effective dopant than Na. By introducing Li, the electrical and thermal transport properties were optimized collectively. The electrical transport properties were boosted remarkably via adjusting carrier concentration, and the maximum power factor (PF) of 11.5 W/cmK and average power factor (PF) ~9.9 W/cmK between 423 and 730 K in PbLiS were achieved, which are much higher than those (9.5 and ~7.7 W/cmK) of PbNaS. Doping Li and Na can weaken the lattice thermal conductivity effectively. Combining the enlarged PF with suppressed total thermal conductivity, a maximum ZT ~0.5 at 730 K and a large average ZT ~0.4 at 423-730 K were obtained in -type PbLiS, which are higher than ~0.4 and ~0.3 in -type PbNaS, respectively.
硫化铅是碲化铅热电材料的潜在替代品，这是由于其在低成本和地球丰度方面的优势。在此，研究了通过掺杂碱金属（钠和锂）的n型硫化铅的热电输运性质，并证实锂是比钠更有效的掺杂剂。通过引入锂，电输运和热输运性质得到了共同优化。通过调节载流子浓度，显著提高了电输运性质，在PbLiS中，在423至730 K之间实现了约11.5 W/cmK的最大功率因子（PF）和约9.9 W/cmK的平均功率因子（PF），这远高于PbNaS的（约9.5和约7.7 W/cmK）。掺杂锂和钠可以有效地降低晶格热导率。结合增大的PF和抑制的总热导率，在n型PbLiS中，在730 K时获得了最大ZT约0.5，在423 - 730 K时获得了较大的平均ZT约0.4，分别高于n型PbNaS中的约0.4和约0.3。
