Ag 2 Q-Based (Q = S, Se, Te) Silver Chalcogenide Thermoelectric Materials.

Thermoelectric technology provides a promising solution to sustainable energy utilization and scalable power supply. Recently, Ag 2 Q-based (Q = S, Se, Te) silver chalcogenides have come forth as potential thermoelectric materials that are endowed with complex crystal structures, high carrier mobility coupled with low lattice thermal conductivity, and even exceptional plasticity. This review presents the latest advances in this material family, from binary compounds to ternary and quaternary alloys, covering the understanding of multi-scale structures and peculiar properties, the optimization of thermoelectric performance, and the rational design of new materials. The "composition-phase structure-thermoelectric/mechanical properties" correlation is emphasized. Flexible and hetero-shaped thermoelectric prototypes based on Ag 2 Q materials are also demonstrated. Several key problems and challenges are put forward concerning further understanding and optimization of Ag 2 Q-based thermoelectric chalcogenides.