LAUSR

Abstract PbTe-based thermoelectric materials are considered to be a medium-temperature thermoelectric candidates and the high-performance n-type PbTe is urgently to be developed to match its p-type counterpart on account of practical application. Herein, we firstly optimized the carrier density of n-type PbTe through Sb doping, and obtained a maximum ZT value of ∼1.0. Then, based on the optimized carrier density, we introduced ternary compounds AgSb(Se, Te)2 to suppress the lattice thermal conductivity. Minimum lattice thermal conductivity of n-type PbTe was reduced as low as ∼0.53 W m−1K−1 and ∼0.62 Wm−1K−1 through introducing AgSbSe2 and AgSbTe2, respectively. Combining the maintained electrical properties with suppressed thermal conductivity, maximum ZT values ∼1.2 and ∼1.3 were obtained in PbTe+2%AgSbSe2 and PbTe+2%AgSbTe2, respectively. This work provides an effective strategy of synergistically balancing charge and phonon transports in n-type PbTe with ternary AgSb(Se, Te)2 compounds.