Advances in silver-based chalcogenide flexible thermoelectric materials

Abstract

Thermoelectric generators (TEGs) can directly convert low-grade thermal energy into electrical energy, possessing numerous benefits, including noise-free operation, pollution-free energy conversion, and long service life. Flexible TEGs can not only fit various curved surfaces but also withstand bending and twisting. This character makes them particularly suitable for wearable power generation technologies and raises considerable interest among people. Silver-based chalcogenide compounds, known for their excellent near-room-temperature thermoelectric properties and ductility, are considered ideal materials for constructing high-performance flexible or wearable TEGs. This study reviews the latest research on flexible thermoelectric materials derived from silver chalcogenides, focusing primarily on Ag–S, Ag–Se, and Ag–Te-based compounds and their composites. Among them, this review pays more attention to pure Ag₂Se and Ag₂Se-based materials because their performance is outstanding. Additionally, the key challenges hindering the enhancement of thermoelectric performance in these materials have also been discussed. Finally, the prospects for the development and application of silver chalcogenide-based flexible thermoelectric materials have been outlined.