High-entropy-stabilized chalcogenides with high thermoelectric performance

Thermoelectric technology generates electricity from waste heat, but one bottleneck for wider use is the performance of thermoelectric materials. Manipulating the configurational entropy of a material by introducing different atomic species can tune phase composition and extend the performance optimization space. We enhanced the figure of merit ( ) value to 1.8 at 900 kelvin in an n-type PbSe-based high-entropy material formed by entropy-driven structural stabilization. The largely distorted lattices in this high-entropy system caused unusual shear strains, which provided strong phonon scattering to largely lower lattice thermal conductivity. The thermoelectric conversion efficiency was 12.3% at temperature difference Δ = 507 kelvin, for the fabricated segmented module based on this n-type high-entropy material. Our demonstration provides a paradigm to improve thermoelectric performance for high-entropy thermoelectric materials through entropy engineering.