Deviceization of high-performance and flexible Ag ₂Se films for electronic skin and servo rotation angle control

Abstract

Ag ₂Se shows significant potential for near-room-temperature thermoelectric applications, but its performance and device design are still evolving. In this work, we design a novel flexible Ag ₂Se thin-film-based thermoelectric device with optimized electrode materials and structure, achieving a high output power density of over 65 W m ⁻² and a normalized power density up to 3.68 μW cm ⁻² K ⁻² at a temperature difference of 42 K. By fine-tuning vapor selenization time, we strengthen the (013) orientation and carrier mobility of Ag ₂Se films, reducing excessive Ag interstitials and achieving a power factor of over 29 μW cm ⁻¹ K ⁻² at 393 K. A protective layer boosts flexibility of the thin film, retaining 90% performance after 1000 bends at 60°. Coupled with p-type Sb ₂Te ₃ thin films and rational simulations, the device shows rapid human motion response and precise servo motor control, highlighting the potential of high-performance Ag ₂Se thin films in advanced applications.

Abstract

The authors design a flexible Ag ₂Se-based thermoelectric device with optimized electrode materials, structure, and selenization time, capable of various applications including rapid response to human motion signals as electronic skin.