Boosting the thermoelectric properties of n-type PbSe through the dual incorporation of Sb and Al

PbSe has attracted significant attention as a medium-temperature thermoelectric (TE) material due to its abundance and low cost. This study demonstrate that in the novel thermoelectric system of Al x Pb 0.9975 Sb 0.0025 Se samples ( x = 0, 0.005, 0.01, 0.02, and 0.03), the electronic conductivity of pure PbSe was enhanced by Sb doping. Introducing a small amount of Al to occupy the Pb vacancies not only increases the Hall carrier concentration in PbSe, but also resulting in an increase in Seebeck coefficient ( S ). At 873 K, the power factor ( PF ) of the sample with x = 0.02 increases to 16 μW cm −1 K −2 . In addition, the total thermal conductivity did not increase significantly, so the thermoelectric performance was effectively improved, a maximum figure of merit ( ZT ) of 1.8 is achieved at 873 K, along with a high average ZT ( ZT avg ) of approximately 1 over the temperature range of 300–873 K.