Cost-Effective Symmetric PbSe-Based Device for Thermoelectric Cooling.

Xu, Liqing; Hong, Tao; Liu, Shibo; Wang, Sining; Liu, Dongrui; Zhou, Tianhang; Xiao, Yu; Zhao, Li-Dong · Adv Mater · 2025

basic_science · Level V

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Abstract

Thermoelectric cooling technology has broad applications but is limited by the high cost of tellurium (Te) in commercially available Bi<sub>2</sub>Te<sub>3</sub>-based thermoelectric materials. Herein, a cost-effective symmetric PbSe-based device constructed from 7 pairs of Pb<sub>0.988</sub>Cu<sub>0.002</sub>Se (p-type) and Pb<sub>1.02</sub>Cu<sub>0.002</sub>Se (n-type) is presented, which demonstrates impressive cooling temperature difference (ΔT<sub>C</sub>) of 32.8 and 41.0 K with the hot side maintained at 303 and 343 K, respectively. This low-cost symmetric PbSe-based device exhibits superior cost-effectiveness (ΔT/cost) for near-room-temperature thermoelectric cooling compared to other Bi<sub>2</sub>Te<sub>3</sub>-based devices. Its high cooling performance primarily stems from an advanced carrier and phonon transport properties in p-type Pb<sub>0.988</sub>Cu<sub>0.002</sub>Se. Specifically, Pb vacancy and Cu substitution in Pb<sub>0.988</sub>Cu<sub>0.002</sub>Se act as strong p-type dopants that effectively optimize carrier density, resulting in a maximum power factor of 28.69 µW cm<sup>-1</sup> K<sup>-2</sup> at room temperature. Moreover, the mobile Cu atoms within the lattice significantly impede phonon propagation, leading to a low room-temperature lattice thermal conductivity of 1.10 W m<sup>-1</sup> K<sup>-1</sup>. Finally, the room-temperature figure of merit (ZT) and average ZT value in p-type Pb<sub>0.988</sub>Cu<sub>0.002</sub>Se can reach 0.6 and 0.68 at 300-573 K, surpassing previous p-type PbSe-based polycrystals. This work emphasizes the significant potential of a cost-effective PbSe compound for near-room-temperature cooling applications.