Synergistically optimizing electrical and thermal transport properties of n-type PbSe

this paper, we report that the thermoelectric performance of n-type PbSe could be improved through synergistically optimizing electrical and thermal transport properties via Sb doping and Mg alloying. The carrier concentration was firstly optimized through Sb doping, resulting in a maximum power factor of similar to 15.4 mu Wcm(-1) K-2 and maximum ZT of similar to 0.9 at 873 K in Pb0.99Sb0.01Se. Then, Mg was selected for alloying in Pb sites to produce point defects, which can largely intensify the phonon scattering and lower thermal conductivity. After Mg alloying, the thermal conductivity at 300 K (873 K) was significantly suppressed from similar to 4.6Wm(-1) K-1 (1.5Wm(-1) K-1) for Pb0.99Sb0.01Se to similar to 2.9Wm(-1) K-1 (1.1Wm(-1) K-1) for Pb0.99Sb0.01Se-6% MgSe. Through combining Sb doping and Mg alloying, a maximum ZT of similar to 1.1 was achieved at 873 K for Pb0.99Sb0.01Se-6% MgSe, and the average ZT (ZTave) was increased by 28.6% from similar to 0.42 for Pb0.99Sb0.01Se to similar to 0.54 for Pb0.99Sb0.01Se-6% MgSe. The results indicate that PbSe is a robust candidate for medium-temperature thermoelectric applications.