Integrated Physical Vapor Deposition and Vapor Reaction Approach Advances High‐Performance Flexible Ag 2 Te Thin‐Film Thermoelectrics

ABSTRACT Ag 2 Te possesses both promising thermoelectric potential and intrinsic plasticity, making it a strong candidate for flexible thermoelectrics. However, optimizing the thermoelectric performance and simplifying the fabrication process of Ag 2 Te thin films remain challenging. Here, we introduce a straightforward strategy that combines physical vapor deposition (PVD) with chemical vapor reaction to synthesize Ag 2 Te, while avoiding Te‐induced damage to the PVD chamber. In the Ag 2 Te thin films prepared through this unique process combination, the dispersed and uniformly distributed residual Ag forms carrier channels, resulting in ultrahigh electrical conductivity, thereby achieving a record‐high power factor of 23.8 µW cm −1 K −2 at room temperature. Moreover, the films demonstrate excellent mechanical flexibility, maintaining resistance variations within 10% after 1000 bending cycles at a bending radius of 5 mm. A six‐leg device assembled from these films delivers a maximum output power exceeding 500 nW under a temperature difference of 23 K, corresponding to a normalized power density of ∼5 µW cm −2 K −2 . This work provides a facile route for synthesizing Ag 2 Te thin films and highlights their potential for practical flexible thermoelectric applications.