AgSbSe 2 is a typical member of cubic I−V−VI 2 semiconductors, which are known for their extremely low lattice thermal conductivity (κ l ). However, the low electrical conductivity of AgSbSe 2 , below ∼10 S cm −1 at room temperature, has hindered its thermoelectric performance. In this work, single-phase AgSbSe 2 bulk samples with much higher electrical conductivity were synthesized via self-propagating hightemperature synthesis (SHS) combined with spark plasma sintering (SPS) for the first time. Pb doping through the nonequilibrium process further increases the electrical conductivity to >100 S cm −1 . Furthermore, continuously increased effective mass m d * can be achieved upon Pb doping because of the multiple degenerate valence bands of AgSbSe 2 and the energy-filtering effect induced by in situ-formed nanodots. The simultaneous enhancement of both the electrical conductivity and Seebeck coefficient contributes to an unprecedentedly high average power factor of 6.75 μW cm −1 K −2 . Meanwhile, the introduced dense grain boundaries and point defects enhance the phonon scattering and consequently suppress κ l , yielding a high ZT value of 1.2 at 723 K in AgSb 0.94 Pb 0.06 Se 2 . This study opens a new avenue for rapid, low-cost, large-scale production of AgSbSe 2 -based materials and demonstrates that Pb-doped AgSbSe 2 prepared via the SHS−SPS method is a promising candidate for thermoelectric applications.

Active Peltier cooling enables Peltier heat transfer in addition to the traditional Fourier thermal conductance, which is useful in some special applications, such as the microthermostats. From the material wise, however, the study on the active Peltier cooling materials is rare. We carried out a high-throughput workflow to screen out 5 room-temperature active Peltier cooling materials, GaSbLi2, HgPbCa2, SnTiRu2, GeYbLi2, and GeTiFe2, from 2958 Heusler materials. All the five materials are semimetals or very narrow band gap systems with high electrical conductivity. Some of these materials have relatively large Seebeck coefficients due to the band asymmetry. Their effective thermal conductivity κeffs, which are the summation of active Peltier thermal conductivity and passive thermal conductivity, are all greater than Cu at the room temperature and ΔT = 1 K. The present work gives a possible way to search active cooling Peltier materials for the applications of precise temperature control.

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