Grid-plainification enables medium-temperature PbSe thermoelectrics to cool better than Bi ₂ Te ₃

Abstract

Thermoelectric cooling technology has important applications for processes such as precise temperature control in intelligent electronics. The bismuth telluride (Bi ₂ Te ₃ )–based coolers currently in use are limited by the scarcity of Te and less-than-ideal cooling capability. We demonstrate how removing lattice vacancies through a grid-design strategy switched PbSe from being useful as a medium-temperature power generator to a thermoelectric cooler. At room temperature, the seven-pair device based on n-type PbSe and p-type SnSe produced a maximum cooling temperature difference of ~73 kelvin, with a single-leg power generation efficiency approaching 11.2%. We attribute our results to a power factor of >52 microwatts per centimeter per square kelvin, which was achieved by boosting carrier mobility. Our demonstration suggests a path for commercial applications of thermoelectric cooling based on Earth-abundant Te-free selenide-based compounds.

Editor’s summary

Thermoelectric cooling is an attractive solid-state method, but it currently relies on resource-limited telluride-based materials. Qin et al . discovered a relatively simple lead selenide–based material that has attractive cooling potential (see the Perspective by Jakhar and Ibáñez). They found compositions in which extra lead added to the system helped to fill in vacancies, thus improving the thermoelectric efficiency. By pairing this material with tin selenide, the authors built a cooling device that has relatively attractive performance and demonstrates the potential for tellurium-free cooling. —Brent Grocholski

Abstract

Lattice plainification using a grid-design strategy facilitates superior cooling capability in medium-temperature lead selenide thermoelectrics.