RESUMEN
Among inorganic thermoelectric materials, flexible thermoelectric materials have attracted considerable attention. In this study, highly flexible and plastically bendable silver selenide films with excellent thermoelectric performance at room temperature are presented. The flexibility of the freestanding silver selenide films was significantly improved through a simple annealing treatment. The highly flexible silver selenide films with a thickness of 26.0 µm displayed outstanding n-type thermoelectric performance, achieving an in-plane zT value of 0.38 at room temperature. Because silver selenide films are plastically bendable with a bending radius of less than 1 mm, they can be shaped into various forms. To achieve stretchability and skin-conformality in the thermoelectric generator, S-shaped silver selenide strips were used as an n-type thermoelectric element. Effective harvesting of electricity from heat of the human body was successfully demonstrated.
RESUMEN
Thermoelectric inorganic films are flexible when sufficiently thin. By removing the substrate, that is, making them free-standing, the flexibility of thermoelectric films can be enhanced to the utmost extent. However, studies on the flexibility of free-standing thermoelectric inorganic films have not yet been reported. Herein, the high thermoelectric performance and flexibility of free-standing thermoelectric Ag2Se films are reported. Free-standing Ag2Se films with a thickness of 25.0 ± 3.9 µm exhibited an in-plane zT of 0.514 ± 0.060 at room temperature. These films exhibited superior flexibility compared to Ag2Se films constrained on a substrate. The flexibility of the Ag2Se films was systematically investigated in terms of bending strain, bending radius, thickness, and elastic modulus. Using free-standing Ag2Se films, a substrate-free, flexible thermoelectric generator was fabricated. The energy-harvesting capacity of the thermoelectric generator was also demonstrated.
