An approach of enhancing thermoelectric performance for p-type PbS: Decreasing electronic thermal conductivity.

In this work, the thermoelectric performance of p -type PbS was boosted remarkably through Na doping and introducing Cu 2 S. Firstly, the electrical transport properties (power factor) of p -type PbS was optimized via Na doping, and the maximum ZT ∼ 0.67 was achieved in Pb 0.98 Na 0.02 S. Secondly, the total thermal conductivity of Pb 0.98 Na 0.02 S was suppressed through introducing Cu 2 S by means of significantly reducing the electronic thermal conductivity by 80% at 823 K through Cu counter-doping, meanwhile, the power factor of Pb 0.98 Na 0.02 S was further enhanced through optimizing carrier concentrations via introducing Cu. The combination of decreasing total thermal conductivities and the optimizing power factors leads to peak ZT ∼1.2 at 823 K in p -type Pb 0.98 Na 0.02 S–2%Cu 2 S. Present results illustrate that introducing Cu 2 S is an effective method to enhance the thermoelectric performance of p -type PbS through decreasing the electronic thermal conductivity which also has great potential in other thermoelectric materials system. • Thermoelectric performance of p -type PbS was remarkably boosted by reducing electronic thermal conductivity κ ele. • κ ele of p -type Pb 0.98 Na 0.02 S was reduced by 80% from ∼0.53 W m−1K−1 to ∼ 0.11 W m−1K−1 at 823 K with introducing Cu 2 S. • The maximum ZT ∼1.2 at 823 K was realized in p -type Pb 0.98 Na 0.02 S–2%Cu 2 S. [ABSTRACT FROM AUTHOR]